Endurance training in patients with multiple sclerosis: five case studies.Patients with multiple sclerosis (MS) exhibit various symptoms such as weakness, ataxia ataxia (ətăk`sēə), lack of coordination of the voluntary muscles resulting in irregular movements of the body. Ataxia can be brought on by an injury, infection, or degenerative disease of the central nervous system, e.g. , increased reflex activity, and sensory disturbances depending on the site of the pathological processes in the central nervous system (CNS See Continuous net settlement. CNS See continuous net settlement (CNS). ).[1,2] The onset of MS often occurs between the ages of 20 and 30 years.[3] Even though these patients are often young and initially exhibit barely perceptible symptoms, there will be a decrease in optimal physical activity.[4] General fatigue is a dominating problem for the majority of patients with MS.[5,6] This fatigue is believed to have a central origin.[5] Using electrical stimulation[7] or [p.sup.31] magnetic resonance magnetic resonance, in physics and chemistry, phenomenon produced by simultaneously applying a steady magnetic field and electromagnetic radiation (usually radio waves) to a sample of atoms and then adjusting the frequency of the radiation and the strength of the spectroscopy,[8] however, it has been found that patients with upper motoneuron motoneuron /mo·to·neu·ron/ (mot?o-nldbomacr´on) motor neuron; a neuron having a motor function; an efferent neuron conveying motor impulses. injury have peripheral changes in their muscles that also could contribute to the perception of general fatigue. Decreases in isokinetic isokinetic /iso·ki·net·ic/ (-ki-net´ik) maintaining constant torque or tension as muscles shorten or lengthen; see isokinetic exercise, under exercise. peak torque of single or repeated knee flexions in patients with MS have been reported by several authors.[9,10] Patients who have positive Babinski signs as their only symptom will have generally increased reflex activity after exertion and will need a longer period of time to recover after fatigue as compared with subjects with no known neurological impairment.[11] Patients with increased reflex activity in the lower extremities will have difficulty relaxing their extensor muscles Extensor muscles A group of muscles in the forearm that serve to lift or extend the wrist and hand. Tennis elbow results from overuse and inflammation of the tendons that attach these muscles to the outside of the elbow. Mentioned in: Tennis Elbow and activating their flexor flexor /flex·or/ (flek´ser) 1. causing flexion. 2. a muscle that flexes a joint. flexor retina´culum see entries under retinaculum. muscles after exertion.[10] Delisa et al[1] proposed that the physical training of patients with MS should be submaximal to avoid fatigue reactions. The clinical experience of endurance training Endurance training is the deliberate act of exercising to increase stamina and endurance. Exercises for endurance tends to be aerobic in nature versus anaerobic movements. Aerobic exercise develops slow twitch muscles. for patients with MS, however, is often positive. The day-to-day variation in the actual symptoms reported by patients with MS makes it difficult to devise generalized training studies and physical therapy regimens. Moreover, Delisa et al,[1] based on their clinical experience, stated that the fatigue is not decreased by strengthening exercise in these patients. In contrast, Gehlsen at al[12] investigated the effects of an aquatic program on the isokinetic force production and endurance of patients with MS and generally reported positive changes in force production, fatigue, work, and power. Positive experiences after training or rehabilitation in activities such as climbing stairs, dressing, and transferring have also been reported for patients with severe MS.[13] Some physical training studies,[14,15] have demonstrated that exercise can induce positive mood changes in healthy subjects and that exercise has antidepressant antidepressant, any of a wide range of drugs used to treat psychic depression. They are given to elevate mood, counter suicidal thoughts, and increase the effectiveness of psychotherapy. effects in depressed patients. it would be interesting to investigate whether such positive changes also occur in patients with MS. In several endurance studies,[16-20] isokinetic dynamometry dy·na·mom·e·ter n. Any of several instruments used to measure mechanical power. [French dynamomètre : Greek dunamis, power; see dynamic + -mètre, -meter. has been combined with electromyographic (EMG EMG abbr. electromyogram Electromyography (EMG) A diagnostic test that records the electrical activity of muscles. ) recordings of the muscle group under investigation. The mean power frequency (MPF MPF mitosis-promoting factor. ) shift of the EMG signal toward lower frequencies has been extensively used to indicate the development of peripheral fatigue.[21,22] Gerdle and colleagues[18,23] have found that the behavior of the MPF generally predicts the mechanical performance (ie, peak torque or work) of upper- and lower-limb muscles in healthy subjects. By combining dynamometry and MPF, the origin (central or peripheral) of the decrease in mechanical performance can be determined. Hence, a decrease in mechanical output without a shift in MPF toward lower frequencies is most likely to be of central origin. This study of endurance training in patients with MS was intended primarily to answer the following questions: 1. Will endurance training of the knee flexors of patients with MS lead to increased mechanical output throughout repetitive isokinetic contractions? 2. Will endurance training lead to a decreased perception of fatigue throughout a standardized endurance test endurance test n → prueba de resistencia endurance test n → test m d'endurance endurance test endurance n ? 3. Are positive changes in the subjective reports concerning physical well-being and fatigue parallel to changes in mechanical performance (peak torque) and MPF of repeated isokinetic knee flexions? Method Subjects Five patients with the diagnosis of MS volunteered for the study. They were selected from the neurological department of the university hospital of Umea, Sweden. It was 6 to 20 years since they were first diagnosed. The patients were graded according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. the Kutzke Expanded Disability Scale (EDSS EDSS Expanded Disability Status Scale EDSS Equine Digit Support System EDSS Executive Decision Support System EDSS Equipment Deployment and Storage System EDSS Electronic Document Storage System EDSS Electronic Data Storage System EDSS Electronic Document Submission System ).[24] The EDSS is a functional disability scale designed to evaluate the ambulatory status of patients with MS. The scale is graded from 0 to 10. Grade 0 denotes no disturbances; grade 5 denotes the patient is ambulatory without help or resting for 200 m, but the disturbance restricts the patient's activity throughout the day; and grade 7 denotes that the patient is able to walk about 5 m but needs assistance.24 Different definitions of spasticity spasticity /spas·tic·i·ty/ (spas-tis´i-te) the state of being spastic; see spastic (2). spas·tic·i·ty n. 1. A spastic state or condition. 2. Spastic paralysis. exist; for the purposes of our study, we used the definition given by Lance: [Spasticity] a motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with exaggerated tendon jerks, resulting from hyperexitability of the stretch reflex, as one component of the upper motor neurone neu·rone n. Chiefly British Variant of neuron. syndrome.[25] The degree of hypertonia hypertonia /hy·per·to·nia/ (-to´ne-ah) a condition of excessive tone of the skeletal muscles; increased resistance of muscle to passive stretching. hy·per·to·ni·a n. of the legs was classified according to the modified Ashworth scale (0-4),[26] which is a standardized scale for documenting resistance to passive movements. Grade 0 denotes no increase in muscle tone, and grade 4 denotes that the affected body part is rigid in flexion flexion /flex·ion/ (flek´shun) the act of bending or the condition of being bent. flex·ion n. 1. The act of bending a joint or limb in the body by the action of flexors. 2. or extension. Each subject was positioned supine during the grading of the tonus tonus /to·nus/ (to´nus) tone or tonicity; the slight, continuous contraction of a muscle, which in skeletal muscles aids in the maintenance of posture and in the return of blood to the heart. of the lower limb. The tonus was registered for the limb that showed the most reflex activity. The following descriptions of the subjects include the clinical signs observed when they moved freely. Subject A. This subject (age = 39 years, weight = 54 kg, height = 168 cm) had known her diagnosis for 6 years and was in a stable state throughout the test period. She was graded 2 according to the EDSS. Her walking capacity was more than 1,000 m. Beyond this distance, however, feelings of general fatigue and stiffness in the right leg increasingly occurred and restricted her walking. No symptoms were visible when she was walking and moving in a general manner, but running or walking quickly induced increased tonus, mostly in the right leg. Her tonus was graded 0 in the right leg according to the modified Ashworth scale. The subject was prescribed 1.00 mg of thiamine chloride daily. Subject B. This subject (age = 41 years, weight = 74 kg, height = 176 cm) had known his diagnosis for 10 years. He was in a stable state throughout the study. His clinical symptoms were graded 4 according to the EDSS. This subject had increased tonus (hyperactive hy·per·ac·tive adj. 1. Highly or excessively active, as a gland. 2. Having behavior characterized by constant overactivity. 3. Afflicted with attention deficit disorder. reflexes) in the lower limbs, which was more pronounced in the right leg. His walking capacity was approximately 1,000 m. He could not run, presumably pre·sum·a·ble adj. That can be presumed or taken for granted; reasonable as a supposition: presumable causes of the disaster. due to increased extensor extensor /ex·ten·sor/ (-ser) [L.] 1. causing extension. 2. a muscle that extends a joint. ex·ten·sor n. A muscle that extends or straightens a limb or body part. tonus in the limbs. The tonus in the right leg was graded 1 according to the modified Ashworth scale. The subject received 10 mg of baclofen two times per day. Subject C. This subject (age = 30 years, weight = 67 kg, height = 174 cm) had known his diagnosis for 10 years. He had grade 6 on the EDSS. His walking capacity was 200 m. For longer distances, he used a wheelchair. When he walked, an increase in extensor tonus in both legs (more pronounced in the right leg) was observed. This increase in tonus appeared to impair his gait. He also showed slight ataxia when walking. The tonus in both legs was graded 1 on the modified Ashworth scale. The subject received 20 mg of baclofen daily. Subject D. This subject (age = 44 years, weight = 67 kg, height = 162 cm) had known her diagnosis for 14 years and was in a stable state throughout the test period. She was graded 6 on the EDSS. She had increased tonus in the extensors of the right leg and experienced difficulty in activation of the dorsal extensors of the right foot. Her walking capacity was approximately 100 m. When ambulating, an orthosis orthosis /or·tho·sis/ (or-tho´sis) pl. ortho´ses [Gr.] an orthopedic appliance or apparatus used to support, align, prevent, or correct deformities or to improve function of movable parts of the body. for the right foot and the support of a crutch crutch (kruch) a staff, ordinarily extending from the armpit to the ground, with a support for the hand and usually also for the arm or axilla; used to support the body in walking. crutch n. were used. Tonus in the right leg was graded 1 according to the modified Ashworth scale. The subject received 25 mg of amitriptyline hydrochloride amitriptyline hydrochloride Apo-Amitriptyline, Levate (CA), Novotriptyn (CA) Pharmacologic class: Tricyclic compound Therapeutic class: Antidepressant Pregnancy risk category D twice per day and 1 mg of estradiol once per day.Subject E. This subject (age = 37 years, weight = 57 kg, height = 168 cm) had known her diagnosis for 20 years. She was graded 7 on the EDSS. She was able to take a few steps with support, but with an increased tonus in the lower limbs and with more marked hypertonus in the right leg. The subject also exhibited increased tonus in her right arm. For ambulation am·bu·late intr.v. am·bu·lat·ed, am·bu·lat·ing, am·bu·lates To walk from place to place; move about. [Latin ambul , she was dependent on a wheelchair, which she could handle herself even outdoors. Her tonus was graded 2 in the right leg according to the modified Ashworth scale. The subject received 25 mg of maprotiline hydrochloride ma·pro·ti·line hydrochloride n. An antidepressant that is chemically similar to tricyclic antidepressants and that inhibits neuronal reuptake of norepinephrine. twice per day. Ten female subjects without known neurological impairment, aged 25 to 40 years (X = 33, SD = 4) performed the same isokinetic endurance tests at one occasion and served as a control group. The results from these tests are reported in detail elsewhere.[27] Data from these subjects are presented to give the reader a representative picture of how the investigated variables will change throughout repeated isokinetic contractions (ie, the pattern). Similar patterns for the investigated variables have described elsewhere.[16-20,23] The absolute levels of peak torque were not comparable because the two groups were not matched with respect to age, gender, anthropometric an·thro·pom·e·try n. The study of human body measurement for use in anthropological classification and comparison. an data, and so forth. Pretraining and Posttraining Tests Each subject performed 50 repeated maximum knee flexions of the limb with the most pronounced symptoms (ie, the limb with most reflex activity) using an isokinetic dynamometer dynamometer /dy·na·mom·e·ter/ (di?nah-mom´e-ter) an instrument for measuring the force of muscular contraction. dy·na·mom·e·ter n. An instrument for measuring the degree of muscular power. .(*) This procedure was repeated at the same time of the day three times before and three times after the training period, with 1 day of rest in between. Each subject was seated in a specially designed chair. The subject was seated with the trunk, the hips, and the noninvestigated thigh fixated fix·ate v. fix·at·ed, fix·at·ing, fix·ates v.tr. 1. To make fixed, stable, or stationary. 2. To focus one's eyes or attention on: fixate a faint object. with straps to enable adequate and comfortable stabilization of the investigated thigh. Great care was taken to align the flexion-extension axis of the the diameter of the sphere which is perpendicular to the plane of the circle. See also: Axis knee joint with the movement axis of the dynamometer and to ensure that the position was maintained throughout the entire test. The lever arm of the dynamometer was fixed at the ankle of the tested leg (see Gerdle et al[28], for details). The passive part of the contraction cycle (ie, the knee extension) was performed manually (ie, against gravity) by the test leader (BS). This was done with the purpose of avoiding an increased tonus in the extensors, which could have reduced the ability for force development in the flexors.[29] No rest was allowed between the active and passive parts of the contraction cycle. The angular velocity was 1.57 rad [s.sup.-1] ([90 [degrees]/s), and the range of motion (ROM) was from 5 to 90 degrees of flexion. A relatively low angular velocity was chosen because patients with increased reflex activity have difficulty performing fast and force-demanding exercises.[30] Electromyographic signals, using surface electrodes(dagger) center-to-center distance = 20 mm), were obtained from the maximum bulges of the semitendinosus and biceps femoris muscles. For both muscles, the electrode placement was 20 cm (SD = 1) proximal from the knee joint. Before the electrodes were attached, the skin area was dry shaved and rubbed with alcohol and ether (4:1). After surface electrodes had been applied, the impedance was checked and only values below 2 k[omega] were accepted. A four-channel preamplifier Preamplifier A voltage amplifier suitable for operation with a low-level input signal. It is intended to be connected to another amplifier with a higher input level. (double dagger double dagger n. A reference mark (  ) used in printing and writing. Also called diesis.Noun 1. ) and a multichannel Using two or more paths for transmission or processing. It can refer to a variety of architectures including (1) multiple I/O channels between the CPU and peripheral devices, (2) multiple wires in a cable, (3) multiple "logical" channels within a single wire or fiber or (4) multiple EMG amplifier(double dagger) (frequency range = 10 Hz-4 kHz [-3 dB]) were used to register the EMG activity. The amplifier was equipped with an adjustable gain, and the gain was individually adjusted in semilogarithmic sem·i·log·a·rith·mic adj. Having one logarithmic and one arithmetic scale: semilogarithmic graph paper. steps to levels suitable for recording. To avoid the influence of artifacts artifacts see specimen artifacts. (eg, from cable movements), the lower cutoff frequency In physics and electrical engineering, the term cutoff frequency or corner frequency represents a boundary in the system response at which energy entering the system begins to be attenuated or reflected instead of transmitted. of 10 Hz was used. An oscilloscope oscilloscope (əsĭl`əskōp'), electronic device used to produce visual displays corresponding to electrical signals. Displays of such nonelectrical phenomena as the variations of a sound's intensity can be made if the phenomena are and an xy-recorder were used continuously to check the signals from the muscles and the dynamometer. The two raw EMG signals, the angle and the torque signals, were simultaneously recorded on a seven-channel, frequency-modulated tape recorder tape recorder, device for recording information on strips of plastic tape (usually polyester) that are coated with fine particles of a magnetic substance, usually an oxide of iron, cobalt, or chromium. The coating is normally held on the tape with a special binder. (section) with a tape speed of 4.75 [cm s.sup.-1] and a frequency range of DC to 1.25 kHz. The signals were analyzed on a computer (Masscomp 5500)(parallel) using a specially designed program. The EMG signals were sampled at a frequency of 4 kHz and analogue-to-digital converted with 12-bit accuracy over the signal range of [+ or -]5 V. The signals were pretreated by mean and trend removal and by Hamming windowing For Northcoast Where we call someone over and then roll our window up on them. Bassline preference. For Example: "Hey, Andi." *insert window being rolled up* "HAHAHA. . Linear drift from the mean during the time window must be removed, otherwise both linear trend and mean will appear as strong components of the low-frequency part of the spectrum.[31] The power spectral density In statistical signal processing and physics, the spectral density, power spectral density, or energy spectral density is a positive real function of a frequency variable associated with a stationary stochastic process, or a deterministic function of time, which has function (PSDF PSDF Power Systems Development Facility ) was obtained (time window=256 milliseconds, bandwidth = 10-500 Hz) using the fast-Fourier transform (FFT (Fast Fourier Transform) A class of algorithms used in digital signal processing that break down complex signals into elementary components. FFT - Fast Fourier Transform ) technique; a 1,024-point FFT yielded a spectral resolution The spectral resolution or resolving power of say a spectrograph, or, more generally, of a frequency spectrum, is a measure of its power to resolve features, say in the electromagnetic spectrum. of approximately 4 Hz. The MPF (mean spectral frequency) was computed. The program also determined peak torque (ie, the peak value of the torque curve throughout the ROM compensated for gravitational grav·i·ta·tion n. 1. Physics a. The natural phenomenon of attraction between physical objects with mass or energy. b. The act or process of moving under the influence of this attraction. 2. torques tor·ques n. Zoology A band of feathers, hair, or coloration around the neck. [Latin torqu ) as the mechanical variable, and the MPF was calculated from the EMG signals of each contraction. For details concerning the method of analysis, see Gerdle et al.[32] For the purposes of this study, we defined strength as the mean value of the peak torque of the first contraction of the three tests done before and after training, respectively. Endurance was defined as the peak torque level of the 50 repeated knee flexions of each test. The mean values of the three tests done before and after training, respectively, were calculated. The isokinetic dynamometer has been used in a number of studies for investigating strength and endurance,[33] and several studies[16,34,35] have examined the reliability and validity of isokinetic peak torques recorded during single or repeated contractions. Surface EMG is widely used, and questions such as normalization In relational database management, a process that breaks down data into record groups for efficient processing. There are six stages. By the third stage (third normal form), data are identified only by the key field in their record. , test-contractions, and EMG-force relationships have been extensively discussed by others.[36,37] The use of EMG (signal amplitude and MPF) during isokinetic contractions has been tested for reliability and validity.[16,38,39] For every fifth contraction of the endurance test, the subject rated the perception of peripheral fatigue of the knee flexors using a 10-point graded scale described by Borg.[40] This scale is recommended for subjective symptoms such as aches, pain, and so on.[40] Ratings of peripheral fatigue using this scale throughout repeated plantar plantar /plan·tar/ (plan´tar) pertaining to the sole of the foot. plan·tar adj. Of, relating to, or occurring on the sole. flexions and shoulder flexions have generally shown a good correlation with peak torque throughout the initial 40 to 50 maximum isokinetic contractions.[18,23] One day before and 1 day after the training period, the subjects rated psychological and physical well-being (satisfaction) in the following areas: general fatigue, general health, physical fitness, somatic somatic /so·mat·ic/ (so-mat´ik) 1. pertaining to or characteristic of the soma or body. 2. pertaining to the body wall in contrast to the viscera. so·mat·ic adj. health, and mood. These items were chosen as relevant for patients with MS. For these ratings, visual analog scales (VAS vas (vas) pl. va´ sa [L.] vessel.va´sal vas aber´rans 1. a blind tubule sometimes connected with the epididymis; a vestigial mesonephric tubule. 2. ) were used. Each of these scales had a total length of 100 mm. The following endpoints were used: for general fatigue, "no fatigue" and "continuous fatigue," respectively; for general health, very good" and very bad," respectively; for physical fitness, "very good" and "very bad," respectively; for somatic health, "very healthy" and "very sick," respectively; and for mood, "not at all depressed" and "very depressed," respectively. In this report, the distances (in millimeters) from the negative endpoints are presented. When completing the VAS posttraining, the subjects were not allowed to see their pretraining responses. Two of these scales (somatic health and mood) were identical to scales used in studies of patients with chronic pain.[41] A discussion of the reliability of these two scales is presented by Johansson.[41] Hence, three new scales were included in this pilot experiment without any reliability or validity studies. Training Program The general aim of the training program was to increase the absolute level of peak torque of the knee flexors throughout repeated maximum knee flexions. We wanted to design a program that avoided feelings of exhaustion during the training sessions but still resulted in better muscular output. Thus, the principle of the program was to have low-load, relatively long pauses of rest between the exercises and at least 1 day of rest between the training sessions. The intention was to perform three sets of exercises, with 10 repetitions of each exercise per set, at each training session (3 x 10). The subjects rested for 1 minute between each set of exercises and for 3 minutes between new exercises. Each training session ended with 10 minutes of rest, with the subjects lying down.[42] Each training session lasted 40 to 90 minutes including shorter pauses. With the purpose of having a high degree of similarity between pretraining and posttraining tests, the training programs of all subjects consisted of at least one exercise that involved maximum knee flexions in the sitting position. Two subjects performed this exercise using a pulley pulley, simple machine consisting of a wheel over which a rope, belt, chain, or cable runs. A grooved pulley wheel like that used for ropes is called a sheave. apparatus, and the other three subjects performed this exercise using the Orthotron[R],(*) an isokinetic training dynamometer. The training was performed using weight cuffs, the pulley apparatus, isokinetic dynamometers, and in some instances manual assistance. It the subjects managed to perform the exercises against resistance, the load throughout the training was 40% to 50% of 1 repetition maximum (RM), defining 1 RM as the maximum load a subject was able to sustain throughout the ROM.[43,44] One RM was determined when the individual training program was designed. If a subject was unable to perform the movement with this load, he or she performed the exercise against the gravitational torque of the limb itself If the subjects wanted to increase the general load in the training program, they were allowed to do that by increasing the number of repetitions and decreasing the duration of the pauses. When using the Orthotron[R], angular velocities between 1.05 and 1.57 rad [s.sup.-1] (60 [degrees]-90 [degrees]/s) were used and the subject was instructed to perform maximal contractions. The reason for choosing the lower angular velocity (ie, 1.05 rad [s.sup.-1]) was that each subject had to perform a whole contraction cycle, and some subjects were not able to do this at the higher angular velocity (ie, 1.57 rad [s.sup.-1]) (probably due to reflex activity). The training of knee flexion in the pulley apparatus was designed according to the same principle as the other exercises when using resistance (ie, using 40%-50% of 1 RM). Training schedule of subject A. Subject A trained 15 times during 6 weeks with at least 1 day between training sessions. She trained both legs. The knee flexors were trained in the Orthotron[R] at the speed of 1.05 rad [s.sup.-1] for the right leg and 1.52 rad [s.sup.-1] for the left leg and in the prone position Word history The word prone, meaning "naturally inclined to something, apt, liable,", is recorded in English since 1382; the meaning "lying face-down" is first recorded in 1578 but is also referred to as "laying down" or "going prone". using the pulley apparatus with the load 50% of 1 RM. The hip flexors In human anatomy, the hip flexors are a group of muscles (including the iliopsoas which passes through the pelvis) that act to flex the femur onto the lumbo-pelvic complex. were also trained in the pulley apparatus in a standing position with a load of 50% of 1 RM. Hip abduction Abduction Balfour, David expecting inheritance, kidnapped by uncle. [Br. Lit.: Kidnapped] Bertram, Henry kidnapped at age five; taken from Scotland. [Br. Lit. was performed lying on the side and hip extension was performed g in the prone position with weight cuffs on the ankles with a load of 50% of 1 RM. The trunk muscles were trained by using the pulley apparatus or in the prone and supine positions using the weight of the trunk as resistance. From the sixth training session, the subject increased the repetitions from three sets of 10 repetitions each to three sets of 15 repetitions each for all exercises, except for the isokinetic training of the knee flexors and the training of the hip flexors. Training schedule of subject B. Subject B trained 15 times throughout 8 weeks and rested at least I day between training sessions. He trained both legs. Knee flexors were trained in the prone position and hip flexors were trained in the standing position using the pulley apparatus with a load of 40% to 50% of 1 RM. The knee flexors were trained at a speed of 1.05 rad [s.sup.-1] for the right leg and 1.52 rad [s.sup.-1] for the left leg in the Orthotron[R]. Hip abduction was performed lying on the side and hip extension was performed lying prone with the weight cuff on the ankles. The load was 50% of 1 RM. During the five initial training sessions, this subject performed three sets of 5 repetitions each and thereafter three sets of 10 repetitions each of all exercises, except for training of the knee flexors using the Orthotron[R], where he managed to perform three sets of 10 repetitions each throughout the whole training period. Training schedule of subject C. This subject trained two or three times a week throughout 6 weeks at a rehabilitation center and continued in a training department near his home for 1 week (ie, the last 3 sessions). He trained for a total of 20 sessions with the specially designed program. At the rehabilitation center, for the days between training sessions, the subject performed balance exercises that were not part of the specially designed program. He trained both legs. Knee flexors were trained in the sitting position and in the prone position using the pulley apparatus (50% of 1 RM). The subject also used the pulley apparatus to train the hip flexors (in the standing position). The load was 50% of 1 RM. Hip abduction was performed in a side-lying position and hip extension was performed in a prone position with the weight cuff on the ankles. The load was 50% of 1 RM. The trunk was trained in prone and supine positions, with the trunk itself as resistance. The program initially consisted of three sets of 10 repetitions each for an exercises, and from the 10th training session the subject increased to three sets of 15 repetitions each. This subject was very dependent on the temperature in the training room. At a high temperature (ie, >22 [degrees] C), he felt more exhausted and had difficulty performing the training. During the fourth week, his status was somewhat poorer with more reflex activity, which reduced the training intensity reduction of repetitions and loads). Training schedule of subject D. Subject D trained at a rehabilitation center for 4 weeks for a total of 12 training sessions, with at least 1 day of rest between training sessions, using a specially designed program that concentrated on the right leg. She trained the knee flexors in a sitting a position using the pulley apparatus. The load was 50% of 1 RM. She also trained the knee flexors and hip extensors in a prone position and the hip abductors in a side-lying position without any weights. The abdominal muscles abdominal muscles Clinical anatomy The large muscles of the anterior abdominal wall–external oblique, internal oblique, rectus abdominalis, which help in breathing, support spinal muscles while lifting, and help maintain abdominal organs and GI tract in their were trained by sit-ups in a supine position. The subject performed three sets of 10 repetitions each of all the exercises, except during the first week of the training period when she performed three sets of 5 repetitions each of the hip extension exercises. On the days between training sessions, she performed light, nonspecific nonspecific /non·spe·cif·ic/ (non?spi-sif´ik) 1. not due to any single known cause. 2. not directed against a particular agent, but rather having a general effect. nonspecific 1. aquatic exercises. Training schedule of subject E. Subject E trained at a rehabilitation center for 5 weeks, for a total of 15 sessions, with the specially designed program concentrated on the right leg. Knee flexors were trained in the Orthotron[R] at 1.52 rad [s.sup.-1], and eccentric contractions were done in the prone position. She needed manual assistance to flex the knee to the position of 90 degrees to be able to perform the eccentric movement. She trained her hip flexors and abductors in the side-lying position and performed the exercises with manual assistance. Hip extension was performed in the prone position with manual assistance. All exercises consisted of three sets at 10 repetitions each. The subject also needed manual assistance when she trained her left leg, but not as much as for the right leg. She trained every second day. On the days between training sessions, she performed light, nonspecific aquatic exercises. Subjects A and B performed their training at the physical therapy department of the university hospital of Umea, Sweden. Subjects C, D, and E trained at a rehabilitation center that mainly specialized in progressive neurological disorders This is a list of major and frequently observed neurological disorders (e.g. Alzheimer's disease), symptoms (e.g.back pain), signs (e.g. aphasia) and syndromes (e.g. Aicardi syndrome). , located 20 km from the university hospital. Data Analysis Our primary intention was to evaluate the subjects individually. For all repeated recordings and ratings of a specific subject, the mean value of the three tests, pretraining and posttraining, respectively, were used in the analyses. Results The subjects without neurological impairments exhibited a decrease of peak torque during the initial 25 contractions followed by a more or less stable level of peak torque during the rest of the test (Fig. 1). For the patients with MS, this clear pattern did not exist (Fig. 2). Hence, during the initial 25 contractions, a great variability in peak torque was found and no marked decrease in peak torque was found for the majority of patients with MS either pretraining or posttraining. Only subjects C and D had patterns of peak torque throughout the test that was to some degree similar to the patterns of peak torque of the control subjects. Three of the patients (subjects A, B, and D) achieved higher peak torque levels throughout the endurance tests after the training. Subject C did not exhibit any change, and subject E showed a decrease in peak torque throughout the posttraining tests (Fig. 2). The decreases in MPF seen in the subjects without neurological impairments throughout the initial 25 to 30 contractions (Fig. 1) were generally not found in the patients with MS (Figs. 3 and 4). The control subjects generally had lower initial MPFs in both muscles than did the patients with MS during the pretraining test. Lower MPFs throughout the posttraining test compared with the pretraining test were found for the semitendinosus muscle semitendinosus muscle see Table 13.4. of all subjects (Fig. 3). No definite change in MPF of the biceps femoris muscle was found when comparing the pretraining and posttraining data (Fig. 4): The changes concerning the endurance test between the pretraining and posttraining conditions have been summarized in Table 1. [TABULAR DATA OMITTED] All subjects demonstrated improvements on the VAS scale concerning the different aspects of perceived physical and mental health, except for subject D, who reported no change in perceived general health (Tab. 2). Both before and after training, more or less linear increases in the perception of fatigue throughout the endurance test were found (Fig. 5). As shown in Figure 5, the perception of fatigue posttraining was generally lower compared with the pretraining condition; only subject D did not show any definite change. Subjects B and C reached maximal ratings in the perception of fatigue both pretraining and posttraining. Their maximal levels ([greater than or equal to] 10), however, were reached after a greater number of contractions posttraining.
Table 2. Differences (in Millimeters) Between Posttraining and
Pretraining Ratings on Visual Analog Scale(a)
General General Physical Somatic
Subject Fatigue Health Fitness Health Mood
A 28 26 21 23 13
B 29 25 25 28 24
C 40 30 75 5 21
D 31 0 75 26 34
E 23 11 61 20 7
(a) Positive value denotes improvement.
Discussion The instability of the clinical picture often seen in patients with MS often makes it difficult to evaluate the effect of training. The patients with MS in this study, however, did not show any changes in their clinical status throughout the training period (except for one subject who had a 1-week period with increased reflex activity). The training and the special design of the program appeared to be well suited for these patients because the effects of training were generally positive from the subjective rating (VAS) point of view. Moreover, the subjects reported such positive experiences whether they had been training alone at a physical therapy department or whether they had been at a rehabilitation center that specialized in progressive neurological disorders. Clear positive effects were not found in the different physiological variables measured even though a majority (three out of five) of the subjects had increased their strength and endurance (Fig. 2), which indicates a physiological improvement as well. It is reasonable to assume that, from the patient's point of view, the aspect of primary importance is to feel better; it is only of secondary importance if this feeling is accompanied by physiological improvements. In the future, research with more subjects must be conducted before making definite statements about the physiological effects of this kind of training program in patients with MS. The fact that muscular endurance increased is consistent with the study of Gehlsen and co-workers,[12] who investigated the effects of an aquatic program and reported generally positive changes in force production, fatigue, power, and work. These physiological improvements are probably of peripheral origin. Hence both biochemical and electrophysiological studies of patients with upper neuron lesions suggest biochemical changes biochemical changes (bī·ō·keˈmik· in the investigated muscles of the lower limb.[7,8] These changes are probably due to the long-term disuse dis·use n. The state of not being used or of being no longer in use. disuse Noun the state of being neglected or no longer used; neglect Noun 1. or altered use of the muscle fibers, as suggested recently by Lenman and co-workers.[7] One of the authors (BS) often has contact with the subjects who participated in this study, and four of them reported that they were able to perform more demanding daily functional activities involving the lower limbs after the training period. Even though subject B did not report any functional improvements, he both rated better on the VAS and exhibited improvements in the endurance/strength test. Another possibility is that the observed increased functional capacity may only be a reflection of increased general well-being or self-confidence.[45] This increased sense of well-being or self-confidence in turn may make the subjects more willing to try and succeed in functional activities near the limit of their capacity. Our belief in the subjects' absolute capacity may also have influenced their functional capacity in a positive way. The patients with MS did not exhibit the same clear pattern of an initial decrease in mechanical output as the control subjects. We have proposed that the initial decrease in mechanical performance during repeated maximal isokinetic contractions in subjects without neurological impairments reflects fatigue mainly of the type II motor units (fibers).[16,23] Consistent with this suggestion, the MPF of the two muscles investigated remained relatively stable throughout the endurance tests for the patients with MS. Thus, even though the patients experienced peripheral fatigue, it was not accompanied by an MPF shift. These findings are consistent with fatigue of mainly central origin, as expected (ie, the frequency spectrum of the EMG signal was dominated by the effects of the upper motoneuron dysfunction). An additional explanation for the stable MPF throughout the endurance tests in the patients with MS could be that due to the pathological changes in the CNS, these patients had difficulties in recruiting their type 11 motor units (associated with decreased strength) and relied primarily on the type I fibers. Some studies indicate that a primary reliance on type I muscle fibers will be associated with a stable MPF.[23] Type II fiber atrophy, without any change in the proportion of the two main fiber types, has also been reported in morphological studies.[46,47] Other studies,[48,49] however, have shown an increased proportion of type Il fibers without any signs of fiber atrophy. Such morphological findings could be consistent with the higher initial MPF of the patients with MS in our study because MPF is positively correlated with the proportion of type II muscle fibers.[28,50] The findings of Edstrom and co-workers,[46,47] however, are not consistent with such an explanation for the higher MPF in patients with MS. Conclusion Our report indicates that patients with MS generally experience increased well-being in different areas. The physiological variables examined, however, did not show such a consistent picture for all patients. Our report indicates potential beneficial effects of endurance training even though research with more patients must be conducted before definite conclusions can be drawn. Acknowledgments We thank Majken Rahm and Monika Edstrom, who assisted during the tests and who also performed the EMG analyses. We also thank Maj-Lis Nordstrom, Sara Wiik, and Anne Wikstrom at Bjorkgarden, who supervised the training for three of the patients. References [1] Delisa JA, Hammond MC, Mikulic MA, Miller RM. Multiple sclerosis, part I: common physical disabilities and rehabilitation. Am Fam Physician. October 1985:157-163. [2] Kraft GH, Freal JE, Coryell JK. Disability, disease duration, and rehabilitation service needs in multiple sclerosis: patient perspectives. Arch Phys Med Rehabil. 1986;67:164-168. [3] Mc Alphine D. Course and Diagnosis in Multiple Sclerosis: A Reappraisal London, England: Churchill Livingstone Imprint of a medical publishing company owned by Elsevier Ltd, but previously owned by Harcourt and Pearsons. Originally formed from Livingstone, Edinburgh, Scotland, and J & A Churchill, London, UK, and subsequently with an office in New York, but now integrated with the rest of ; 1972:197-223. [4] Madonna MG, Holland NJ, Wiesel-Levison P. The value of physical therapy improving gait in multiple sclerosis: a research design. Rehabilitation Nursing. September-October 1985: 32-34. [5] Freal JE, Kraft GH, Coryell JK. Symptomatic fatigue in multiple sclerosis. Arch Phys Med Rehabil. 1984;65:135-137. [6] Ericsson RP, Lie MR, Wineinger MA. Rehabilitation in multiple sclerosis. Mayo Clin Proc. 1989;64:818-828. [7] Lenman AJR AJR American Journal of Roentgenology AJR American Journalism Review AJR Academy for Jewish Religion AJR Association of Jewish Refugees (UK organization) AJR Accelerated Junctional Rhythm , Tulley FM, Vrbova G, et al. Muscle fatigue in some neurological disorders. Muscle Nerve. 1989;12:938-941. [8] Miller RG, Green AT, Moussavi RS, et al. Excessive muscular fatigue in patients with spastic spastic /spas·tic/ (spas´tik) 1. of the nature of or characterized by spasms. 2. hypertonic, so that the muscles are stiff and movements awkward. spas·tic adj. 1. paraparesis paraparesis /para·pa·re·sis/ (-pah-re´sis) partial paralysis of the lower limbs. tropical spastic paraparesis chronic progressive myelopathy. . Neurology. 1990;40:1271-1274. [9] Armstrong LE, Wiandt DM, Swasey PR, et al. Using isokinetic dynamometery to test ambulatory patients with multiple sclerosis. Phys Ther. 1983;63:1274-1279. [10] Dunchan P. The effect of a prior quadriceps contraction on knee flexor torque in normal subjects and multiple sclerosis patients with spastic paraparesis. Physiotherapy Practice. 1987;3:11-17. [11] Benecke R, Condrad B. Evaluation of motor deficits in patients suffering from multiple sclerosis. In: Bauer HJ, Posers S, Ritter rit·ter n. pl. ritter A knight. [German, from Middle High German riter, from Middle Dutch ridder, from r G, eds. Progress in Multiple Sclerosis Research. Berlin, Federal Republic of Germany: Springer-Verlag; 1980:589-595. [12] Gehlsen G, Grigsby S, Winant DM. Effects of an aquatic fitness program on the muscular strength and endurance of patients with multiple sclerosis. Phys Ther. 1984;64:653-657. [13] Greenspun B, Steinemann M, Agru R. Multiple sclerosis and rehabilitation outcome. Arch Phys Med Rehabil. 1987;68:434-437. [14] Steinberg H, Sykes EA. Introduction to symposium on endorphins endorphins (ĕndôr`fĭnz), neurotransmitters found in the brain that have pain-relieving properties similar to morphine. There are three major types of endorphins: beta endorpins, found primarily in the pituitary gland; and enkephalins and and behavioral processes: review of literature on endorphins and exercise. Pharmacol Biochem Behav. 1985;23:857-862. [15] LaFontaine TP, DiLorenzo TM, French PA, et al. Aeorobic exercise and mood: a brief review, 1985-1990. Sports Med. 1992; 13:160-170. [16] Fugl-Meyer AR, Gerdle B, Eriksson BE, Jonsson B. Isokinetic plantar-flexion endurance: reliability and validity of output/excitation measurements. Scand Rehabil Med. 1985;17:47-52. [17] Gerdle B, Hedberg R, Jonsson B, Fugl-Meyer AR. Mean power frequency and integrated electromyogram e·lec·tro·my·o·gram n. Abbr. EMG A graphic record of the electrical activity of a muscle as recorded by an electromyograph. Electromyogram (EMG) of repeated isokinetic plantarflexions. Acta Physiol Scand. 1987;130:501-506. [18] Gerdle B, Elert J, Henriksson-Larsen K. Muscular fatigue during repeated isokinetic shoulder forward flexions in young females. Eur Appl Physiol 1989;58:666-673. [19] Elert J, Gerdle B. The relationship between contraction and relaxation during fatiguing isokinetic shoulder flexions: an electromyographic study. Eur Appl Physiol. 1989;59:303-309. [20] Tesch PA, Dudley GA, Duvoisin MR, et al. Force and EMG signal patterns during repeated bouts of concentric or eccentric muscle actions. Acta Physiol Scand. 1990;138:263-267. [21] Basmajian JV, Deluca CJ. Muscles Alive: Their Functions Revealed by Electromyography electromyography Process of graphically recording the electrical activity of muscle, which normally generates an electric current only when contracting or when its nerve is stimulated. . 5th ed. Baltimore, Md: Williams & Wilkins; 1985. [22] Lindstrom L, Petersen I. Power spectra of myoelectric The electrical signals within the human body that stimulate the muscles to move. The signal, which is less than one millivolt, has an average frequency of about 100Hz. Myoelectric signals are used to move prosthetic limbs. signals: motor unit activity and muscle fatigue. In: Stalberg E, Young R, eds. Clinical Neurophysiology Clinical neurophysiology is a medical speciality that studies the central and peripheral nervous systems through the recording of bioelectrical activity, whether spontaneous or stimulated. In some countries it is a part of neurology, for example USA and Germany. . London, England: Butterworth & Co (Publishers) Ltd; 1981:66-87. [23] Gerdle B, Fugl-Meyer AR. Is the mean power frequency shift of the EMG a selective indicator of fatigue of the fast-twitch motor units? Acta Physiol Scand 1992;145:129-138. [24] Kutzke JF. Rating neurologic impairment neurologic impairment Neurology Any damage to, or deficiency of, the nervous system in multiple sclerosis: an expanded disability scale (EDSS). Neurology. 1983;33:1444-1452. [25] Lance JW. Symposium synopsis. In: Felman RG, Young RR, Koella WP, eds. Spasticity: Disordered Motor Control Chicago, Ill: Yearbook Publishers; 1980:485-494. [26] Bohannon RW, Smith MB. Interrater reliability of a modified Ashworth scale of muscle spasticity. Phys Ther. 1987;67:206-207. [27] Lindstrom B, Gerdle B. The Interrelationship in·ter·re·late tr. & intr.v. in·ter·re·lat·ed, in·ter·re·lat·ing, in·ter·re·lates To place in or come into mutual relationship. in between, EMG, peak torque, and perceived fatigue during repeated maximum isokinetic knee flexion with and without active knee extension. Physiotherapy Theory and Practice. 1994;10:17-25. [28] Gerdle B, Wretling ML, Henriksson-Larsen K. Do the fibre type proportion and the angular velocity influence the mean power frequency of the electromyogram? Acta Physiol Scand. 1988;134:341-346. [29] Knutsson E, Maansson A. Effects on maximal voluntary dynamic muscle strength in spastic patients by the inflow from reciprocal muscles. In: Kondrad B, Bennecke R, Bauer HJ, eds. Die Klinischer Wetrtung der Spastizitet. Stuttgart, Federal Republic of Germany: FK Schattauer Verlag GmbH; 1984:147-153. [30] Chen WY, Person FM, Burnett C. Forcetime measurement of knee muscle function of subjects with multiple sclerosis. Phys Ther. 1987;67:934-946. [31] Marple SL Jr. Digital spectral analysis Spectral analysis may refer to:
i·so·met·ric adj. 1. shoulder forward flexions. Eur Appl Physiol. 1988;57:404-408. [33] Elert J. The Pattern of Activation and Relaxation During Fatiguing Isokinetic Contractions in Subjects With and Without Muscle Pain. Umea, Sweden: Arbete och och interj Scot & Irish an expression of surprise, annoyance, or disagreement Halsa, Vetenskaplig Skriftserie; 1991:47. Dissertation. [34] Cabri JMH JMH Jackson Memorial Hospital JMH Schaumburg, Illinois (Airport Code) JMH JSSIS Message Handler JMH James Monroe High school JMH Joint Message Holder (US DoD) . Isokinetic strength aspects of human joints and muscles. Crit Rev Biomed Eng. 1991;19:231-259. [35] Baltzopoulos V, Brodie DA. Isokinetic dynamometry applications and limitations. Sports Med. 1989;8:101-116. [36] Jarvholm U. On Shoulder Muscle Load: An Experimental Study of Muscle Pressures, EMG, and Blood Flow. Gothenburg, Sweden: University of Gothenburg; 1990. Dissertation. [37] Petrovsky JS Glaser RM, Chandler P, Philips A. Evaluation of the amplitude and frequency components of the surface EMG as an index of muscle fatigue. Ergonomics. 1982;25:213-223. [38] Oberg T. Trapezius tra·pe·zi·us n. A muscle with origin from the superior nuchal line, the external occipital protuberance, the nuchal ligament, the spinous processes of the seventh cervical and thoracic vertebrae, with insertion into the lateral third of the posterior Muscle Fatigue and Electromyographic Frequency Analysis Linkoping, Sweden: Linkoping University; 1992. Dissertation. [39] Shankar S, Gander Gander, town (1991 pop. 10,339), NE Newfoundland, N.L., Canada. Gander's airport, an important base in World War II, is a hub for international flights; it also attracts many refugees. It was the site of a Dec. RE, Brandel BR. Changes in myoelectric signal (MES (Manufacturing Execution Software) Software that provides real time access to plant activities that include equipment, labor, orders and inventory. An MES integrates the data with enterprise resource planning (ERP) systems so that management has complete control of ) power spectra during dynamic contractions. Electroencephalogr Clin Neurophysiol. 1989;73:142-150. [40] Borg G. Psychosocial basis of perceived exertion. Med Sci Sports Exerc. 1982;14:377-381. [41] Johansson F. Patients With Chronic Pain: A Clinical, Pharmacological, and Biochemical Study. Umea, Sweden: Umea University; 1982. Dissertation. [42] Russel R. Disseminated sclerosis Noun 1. disseminated sclerosis - a chronic progressive nervous disorder involving loss of myelin sheath around certain nerve fibers disseminated multiple sclerosis, MS, multiple sclerosis : rest exercise therapy - a progress report. Physiotherapy. 1967;66:77. [43] McCartney N, Moroz D, Gamer SH, McComas A. The effects of strength training in patients with selected neuromuscular neuromuscular /neu·ro·mus·cu·lar/ (-mus´ku-ler) pertaining to nerves and muscles, or to the relationship between them. neu·ro·mus·cu·lar adj. 1. disdorders. Med Sci Sports Exerc. 1987;20:362-367. [44] Saltin B. Muskular anpassning till styrketraning. In: Forsberg A, Saltin B, eds. Styrketraning. Stockholm, Sweden: Idrottens Forskningsrad, Sveriges Riksidrottsforbund, Folksam; 1985:74-81. [45] Morgan PW. Affective beneficence beneficence (b  ·neˑ·fi·s of vigorous physical activity. Med Sci Sports Exerc.
1984;17:94-100. [46] Edstrom L. Selective changes in size of red and
white muscle fibres in upper motor lesions and parkinsonism. J Neurol
Sci. 1970;11:537-550. [47] Edstrom L, Grimby L, Hannerz J. Correlation
between recruitment order of motor units and muscle atrophy Muscle atrophy refers to a decrease in the size of skeletal muscle, which occurs in a variety of settings. Atrophy may or may not be distinct from "sarcopenia", which is the loss of muscle seen in the aged. pattern in
upper lesions: significance of spasticity. Experimentia.
1973;29:560-561. [48] Landin S, Hagenfeldt L, Saltin B, Wahren J. Muscle
metabolism during exercise in hemiparetic patients. Clin Sci R Molecular
Med. 1977;53:257-269. [49] Sjostrom M, Fugl-Meyer AR, Nordin G, Wahlby
L. Poststroke hemiplegia hemiplegia /hemi·ple·gia/ (-ple´jah) paralysis of one side of the body.hemiple´gicalternate hemiplegia paralysis of one side of the face and the opposite side of the body. : crural crural /cru·ral/ (krldbomacr´al) pertaining to the lower limb or to a leglike structure (crus). cru·ral adj. 1. Of or relating to the leg, shank, or thigh. 2. muscle strength and structure. Scand J Rehabil Med Suppl. 1980;7:53-67. [50] Moritani T, Gaffney FD, Carmichael T, Hargis J. Interrelationships among muscle fiber types, electromyogram and blood pressure during fatiguing isometric contraction. In: Winter DA, Norman RW, Wells RP, et al, eds. Biomechanics, IX-A. Champaign, Ill: Human Kinetics Publishers Inc; 1985:5a:287-292. |
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