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The influence of resistance training on the magnitude of change in the resting metabolic rate, program compliance and related obesogenic anthropometric parameters in obese and normal-weight female employees.

1 Introduction

Overweight and obesity is a major health threat to the global corporate environment (Chenoweth, 2011; Kirsten & Karch, 2012). South Africa is no exception and research indicated that 68.0% of employees in 71 companies studied, were overweight and obese (Patel, Goetzel, Beckowski, Milner, Greyling, Da Silva, Kolbe-Alexander, Tabrizi & Nossel, 2013). Therefore, it makes good business sense for companies to invest in health promotion programs in order to improve the overall health of the employees as it may provide company benefits, viz., increased productivity and company image, as well as a decrease in absenteeism, presenteeism and health care costs (Chenoweth, 2011).

Due to the high prevalence of overweight and obesity amongst employees (Kirsten & Karch, 2012) as well as various co-morbidities associated with this condition (Dishman, Heath & Lee, 2013) it is understandable that these obesogenic conditions will receive focused attention from management. An increase in obesity can lead to a significant impact on the incidence of cardiovascular disease (CVD), type 2 diabetes, cancer, osteoarthritis, work disability, and sleep apnea, to mention but a few (WHO, 2014). It may also lead to an increase in the number of years that individuals may suffer from obesity-related morbidity and disability, resulting in a detrimental impact on productivity and financial costs (Conn, Adam, Hafdahl, Cooper, Brown & Lusk, 2009; O' Donnell, 2012). The fact that obesity increases with age, places this health hazard more in the spotlight due to the expanding elderly population (PCFS, 2000).

The traditional concept that obesity is the result of energy imbalance (Swanepoel, 2010) may lead to the possible perception that management of this condition basically boils down to decreasing the energy intake on the one hand and increasing the energy expenditure on the other. If these two aspects are in balance, no excessive body weight should be experienced (Swanepoel, 2010). However, this may be an over simplistic approach, as research has indicated that obesity is a multifactorial problem (PCFS, 2000) which includes genetic (DNA) as well as epigenetic effects (Muller, BosyWestphal & Heymsfield, 2010).

In the management of obesity, the resting metabolic rate (RMR) plays an important role, as it forms the biggest part of the total daily energy expenditure (TDEE) (Wang, Heshka, Gallagher, Boozer, Kotler & Heymsfield 2000; Johnstone, Murison, Duncan, Rance & Speakman 2005; Stiegler & Cunliffe, 2006). On the other hand, it is also known that fat-free mass (FFM), with the musculature of the body forming the largest part, is regarded as the major determinant of RMR (Sparti, Delany, De La Bretonne, Sander & Bray, 1997). Therefore, if the muscle mass can be increased by resistance exercise training, it may lead to an increased RMR, resulting in a significant effect on the energy balance in the long term (Wolfe, 2006), which may facilitate the management of overweight and obesity. This motivated the researchers to investigate this hypothesis in a corporate setting, as traditionally the aerobic component usually forms the main focus of corporate wellness programs.

In order to conserve employee's health, various companies have invested in a variety of intervention regimes to address the health and wellness of their employees (Conn et al., 2009; Speck, Hill, Pronk, Becker & Schmitz, 2010; Kahn-Marshall & Gallant, 2012; Ostbye, Stroo, Brouwer, Petersen, Eisenstein, Fuemmeler, Joyner, Gulley & Dement, 2013). The workplace provides an excellent venue to offer health promotion programs, since employees spend the majority of their awake-time at work (O'Donnell, 2012). Regular exercise is associated with several health benefits however the compliance to exercise training intervention remains a challenge (Ekkekakis & Lind; 2006; Swanepoel, 2010). Exercise scientists should therefore be attentive when designing exercise interventions, and protocols should ensure individualized effort, be costeffective, and result in optimum outcomes (Stiegler & Cunliffe, 2006). Exercise protocols with low frequency are associated with higher rates of compliance and seem more practical for sedentary populations (Ibanez, Izquierdo, Arguelles, Forga, Larrison, Garcia-Unciti, Idoate & Gorostiaga, 2005; Wolfe, 2006).

Evaluation of aerobic and resistance exercise regimens shows that higher intensities result in more beneficial changes with regard to body composition, but this is difficult to achieve in overweight or obese persons due to their low cardiovascular fitness and risk of injury (Stiegler & Cunliffe, 2006) as well as the increased rate of perceived exertion (Ekkekakis & Lind, 2006).

Hence the objective of this study was to determine the influence of resistance training on the magnitude of change in the resting metabolic rate and related obesogenic anthropometric variables and rate of compliance in normal-weight and obese female employees.

2 Methods

2.1 Study design

This study followed the quasi-experimental design, using a pre-test-post-test intervention protocol of 12-weeks. Assessments were performed every 4 weeks in order to assess the magnitude of change in each group over time. The study was approved by the Ethics Committee of the North-West University (NWU-00059-07-S1), and conducted during September-October 2012.

2.2 Participants

An availability sample (n = 77) of premenopausal women (25-35 years), all employed by two companies (educational and financial institutions), in an urban environment, was recruited to participate in the study. From this sample, 36 participants (Age, x = 27.8 [+ or -] 3.8) were selected in the normal-weight group (BMI [less than or equal to] 25 kg x [m.sup.-2]) with 41 participants in the obese group (BMI [greater than or equal to] 30 kg x [m.sup.-2]) (Age, x = 30.6 [+ or -] 4.9).

The following criteria for inclusion in this study were applied, viz., healthy, sedentary (on- and off-job, not doing any structured exercise and being sedentary for the majority of the day), BMI [greater than or equal to] 18 kg x [m.sup.-2], non-smoking, non-hypertensive, non-diabetic and no chronic medication consumption. The usage of contraceptives however was not determined. All participants were informed regarding the assessment procedures and all questions were satisfactorily answered. They were also requested to continue with their normal daily habits (eating and drinking) for the duration of the study, except for the resistance intervention regimen. All of them signed the informed consent form as required.

2.3 Measurements

2.3.1 Resting metabolic rate, Fat-free mass and Fat mass

Resting metabolic rate (RMR), Fat-free mass (FFM) and Fat mass (FM) were determined by means of the BOD POD[R] system, based on air displacement (Life Measurements Instruments) (Siri, 1961). The BOD POD employs the RMR estimation model, designed by Nelson, Weinsier, Long and Schutz (1992). This equation is a validated and cross-validated model that includes both FM and FFM. However, this model might present with large variances to optimally predict RMR for the total population or when differentiated by sex (Nelson et al., 1992).

Participants wore swim suits or underwear as well as a Speedo[R] latex swimming cap and were requested to sit as still as possible while in the BOD POD[R]. They were also requested to remove all jewellery and to be voided before the assessment. A fasting period of 8 hours and a non-exercising period of 12 hours were required prior to the assessments. All measurements were done during the same timeslot (6-8 am) with room temperature kept constant (21-23[degrees]C). Prior to every measurement in the BOD POD[R], all calibrations as suggested by the manufacturers were done in order to ensure high-quality results.

2.3.2 Anthropometry

The following anthropometric measurements were done as suggested by ISAK (International Society for the Advancement of Kinanthropometry) (Marfell-Jones, Olds, Stewart & Carter, 2006) viz.: stature (to the nearest 0.5 cm), using a stadiometer (Seca[R]); body mass (to the nearest 0.5 kg), using an electronic scale (Krupps[R]) calibrated on testing days prior to the measurements; and waist circumference (to the nearest 0.5 cm), using a steel tape (Lufkin[R]). Body mass index (BMI) was calculated by body mass (kg)/stature ([m.sup.-2]), as suggested by the ACSM (2010).

2.4 Intervention program

The intervention program consisted of a resistance circuit training regimen complying with the following principles (Beachle & Earle, 2000) and was design to ensure maximum energy expenditure.

Frequency: 3 x per week

Duration: 40-60 minutes/session for 12 weeks

Type: Circuit program using machines and body weight as exercise resistance

Intensity: Moderate intensity

Progression: Starting at 60% of 1-RM, ending at 65% of 1-RM after 12-weeks

Volume: 3 sets with 15 repetitions per exercise station

Rest: Brief rest periods (30-60 sec) between sets and exercises

Circuit: The circuit consisted of 12 stations focusing on the major body muscles in order to ensure maximum energy expenditure.

2.5 Exercise session:

Each session included the following: 5 minutes of warming-up (cycling/walking), stretching of major muscle groups, viz.; quadriceps, hamstrings, pectoral muscles and the calves (2 x 30 sec/group), 35 minutes resistance program (circuit program), followed by stretching the major muscle groups again (2 x 30 sec/group) as a cool-down phase. The sequence of the program is presented in Table 1.

2.6 Progression

The initial exercise intensity started with 60% of 1-RM and progressed with 1-2% of the 1-RM every four weeks to 65% of 1-RM for the last four weeks of the program. The construction of the program ensured a balanced involvement of all major muscle groups in order to ensure maximum energy expenditure (Beachle & Earle, 2000).

2.7 Exercise log

All participants received a log book to complete after each session. They were requested to record the date, repetitions completed as well as their general feeling. Anything they wished to report to the researchers was also stipulated in the log book. This was kept in the gymnasium and signed by the supervisor on completion of each session. The log book was also used to verify the frequency of participation (compliance). Participants were asked to attend the exercise sessions according to the available time slots which they provided to the supervisory Biokineticist.

2.8 Statistical analyses

Analysis of repeated observations using the Linear Mixed Models procedure was used to evaluate the effect of 12-week resistance training in a group of normal-weight and obese participants. The selected model measures the change in the two groups over different time intervals. Measurements were taken at period 1 (baseline), period 2 (retest, after 4 weeks of training), period 3 (re-test, after 8 weeks of training), and period 4 (re-test, after 12 weeks of training). Practical significance (ES) was regarded as large, ES = > 0.5, moderate, ES = around 0.3 and small, ES = > 0.1 (Field, 2005). All statistical analyses were done using the Statistica Program, Version 11 (Stat soft, Inc., 2013).

3 Results

The results of this study are presented in Table 2 and Figure 1A-G, reflecting the absolute values of each variable over time in the two groups. It should be noted that the % change stipulated in Table 2 represents the % difference from the baseline value to the 12-week value of each variable (% change = Pre - Post value / Pre-value).

The groups differed statistically significantly (p<0.05) from one another as the one group being normal-weight and the other group being obese. However, no statistically significant effect was found between the groups and the changes that occurred over time for all variables. Effect sizes however showed some significant changes over time within the groups.

From Table 2 and Figure 1 A it seems that good compliance was noted in both groups during the first 8 weeks (weeks 4 & 8), with the 8 weeks of attendance significantly better than that of the 4 weeks. During the following 4 weeks (week 12) the normalweight group showed a further practically significant increase in compliance. However, in the case of the obese group, a drop (d = 0.55) of 9.3% occurred in compliance rate, compared to baseline value.

In the normal-weight group (NWG), body mass (BM), body mass index (BMI), waist circumference (WC), fat-free mass (FFM) and resting metabolic rate (RMR) displayed a progressive increase from baseline (although not statistical significant) to the assessment of week 12. It was only the changes in FFM and RMR in weeks 4, 8 and 12 that showed practically significant differences from the prior measurements. In the case of the fat mass (FM), the normal-weight group showed a slight decrease in week 4 with small increases to week 8 and week 12 respectively.

[FIGURE 1 OMITTED]

The obese group showed a different response compared to the NWG in BMI, WC and FM (Figures 1C, D, and E & Table 2) in the week 4 assessment. In the BMI and WC a moderate practically significant (d = 0.30) decrease occurred during the first 4 weeks, with a non-significant increase to week 8 and a decrease again to week 12. This decrease was moderate practically significant only in WC (d = 0.32). In the FFM a small increase was noted in week 4, followed by a practically significant (d = 0.32) decrease to week 8 with another slight increase to week 12. The RMR in the obese group showed a non-significant decrease to week 8, followed by an increase to week 12.

4 Discussion

For the first 4 weeks of the intervention program the two groups managed to attend approximately 9 sessions out of the 12 (Fig. 1A). In the next 4 weeks the average attendance increased to about 10 sessions. However, during the last 4 weeks the obese group showed a 9.3% decrease in their compliance, while the non-obese group increased their compliance (calculated from baseline).

Probably the most significant outcome of this study is the different responses between the two groups regarding the resting metabolic rate (Fig. 1G). In the normal-weight group, a progressive increase occurred in RMR from baseline, with significant increases in weeks 8 (d = 0.35) and 12 (d = 0.58). In the obese group a non-significant decrease in RMR occurred in the assessments of weeks 4 and 8 with an increase to near the baseline value during week 12 (6011.38 vs. 5979.54 kJ x [day.sup.-1], Table 2 & Fig. 1G).

It should also be emphasized that the obese group not only depicted a significantly higher RMR and FFM at all assessment periods compared to the normal-weight group, but that the response over time also differed within the two groups. In the case of the obese group the RMR and FFM virtually stayed the same when the post-intervention (week 12) assessment is compared with baseline. In the case of RMR, a non-significant decrease of 0.5% versus a significant increase of 7.0% in the normal-weight group was noted, while in the FFM a 0.7% decrease occurred in the obese group compared to the 7.8% increase in the FFM in the normal-weight group. The reason for this increase in the normal-weight group may be associated with the increase in FFM (muscle mass) resulting from the resistance training program, which may also cause a reduction in fat mass. This is in line with research by Dolezal & Potteiger (1998) and Lemmer, Ivey, Ryan, Martel, Huribut, Metter, Fozard, Fleg and Hurley (2001).

The data of this study suggests that the normal-weight group responded differently from the obese group of employees following a 12-week resistance training regarding the RMR and other obesogenic anthropometric parameters. Although the reason(s) for this is not entirely clear, various possibilities could be related to the outcomes: Firstly, the obese group showed a significantly higher FFM during the baseline assessment. This is probably a result of the larger total body mass which resulted in muscle adaption during activities of daily living in the obese group. Secondly, and related to the abovementioned, is the indication in literature that obese individuals perceived a higher exertion rate than normal-weight individuals, even with the same workload (Marinov, Konstianev & Turnovska, 2002), which may lead to a less pleasant experience with the intervention program (Ekkekakis & Lind, 2006); hence resulting in a decrease in the compliance rate ([9.3%). This subjective feeling of exertion may also lead the obese group to train against a lower resistance - since the 1-RM is to a certain extent underpinned by the perceived exertion. When taking these outcomes into account, it can be stated that with a decrease in adherence or proper program execution, the training stimulus may decrease, resulting in little or no changes in FFM and /or RMR. This may highlight the importance of continuous motivation of the obese individual as well as proper supervision to ensure correct execution and volume of training. This suggestion is supported by the decrease in compliance of the obese group (Fig 1A) from weeks 8 to 12 as well as the slight and no change in the RMR and FFM of the obese group over the same time interval.

It is known that the compliance with an intervention program poses real challenges to corporate wellness initiatives (Dishman, 1988). In a study of Pollock (1988) he stated that the largest percentage of drop-outs happened to be within the first 12 weeks. This could be related to some of the negative experiences which may lead to poor compliance, viz., lack of progress, boredom etc., (Pollock, 1988). Another possibility for the decrease in compliance beyond week 8 found in the obese group may be rooted in the increased perception of exertion (Ekkekakis & Lind, 2006). According to these authors the reason why obese persons seem less willing than normal-weight individuals to participate and comply with physical activities, remains largely unknown, although it has been indicated that obese persons show a low tolerance to high intensity training (Donnelly, Jacobsen, Jackici, Whatley, Gunderson, Gillespie, Blackburn & Tran, 1992). Researchers also reported higher perceived exertion with the same workload in obese individuals compared to their normal-weight peers (Marinov et al., 2002).

In the normal-weight group, the BMI, WC, FFM and RMR progressively increased from the baseline to the end of the 12 weeks of intervention. It must be noted that it was only the FFM (muscle mass) and RMR that depicted practically significant increase in the assessment of weeks 8 and 12. This indicates that beyond week 4 of resistance training, significant improvement in muscle mass (FFM) occurred which may enhance the RMR (McArdle, Katch & Katch 1996). This is in line with the study of Staron, Karapondo, Kraemer, Fry, Gordon, Falkel, Hageman and Hikidia (1994) which indicated that relative maximal and dynamic strength significantly increased after 8 sessions of heavy-resistance training in men and women. Regarding the fat mass (FM), a small but non-significant decrease occurred in the non-obese group after 4 weeks of training followed by a small increase to week 8 and 12 respectively.

In the obese group, the BMI (d = 0.31) and WC (d = 0.32) showed a decrease after 4 weeks of training, followed by a slight increase again to 8 weeks, with a further decrease to the assessment of week 12. A possible explanation for this phenomenon could be attributed to the drop-out rate that occurred from baseline up to week 4 and thereafter (Table 2). The RMR showed a progressive decrease over 8 weeks of training, with a slight increase to week 12. When results of week 12 in the obese group are compared with their baseline data, a slight decrease occurred in all the obesogenic parameters (9.3%-0.5%) (Table 2). This is in line with findings of other research in which resistance training intervention was applied to obese women (Sarson, Ardis, Ozgen, Topuz & Sermez, 2006).

Obesity and related comorbidities have a clearly measurable impact on physical and mental health, generating considerable direct and indirect health costs. Abegunde, Mathers, Adam, Ortegon and Strong (2007) argued that if nothing is done to reduce the risk of chronic diseases, substantial losses in terms of human life and economic production can be expected. They also projected an estimated 250 million deaths and $84 billion of lost national output during 2006-2015 in the USA. According to Dixon (2010) health specialists should focus on weight loss, as this therapy proves to be the most effective way of addressing obesity and obesity-related comorbidity. From the data provided in this study it appears that a resistance intervention program does not result in the same outcomes between obese and normal-weight female employees. This may be rooted in some psycho-physiological consequences that warrant further research in this respect (Foureaux, De Castro, Pinto & Damaso, 2006). However, evidence exists that resistance exercise combined with an aerobic component forms the ideal intervention prescription (Sarson et al., 2006; Willis, Slentz, Bateman, Shields, Piner & Kraus., 2012). It should be noted that special care should also be taken to ensure sufficient motivation and support for obese employees in order to gain optimal results and program compliance.

5 Limitations

The following limitations should be borne in mind while interpreting the results. A control group would contribute to a better understanding of the influence of a resistance training intervention program on the response in normal-weight and obese female employees. However, the small numbers that volunteered for the study as well as the anticipated drop-outs led the authors to decide to sacrifice the control group. A significant drop-out in the obese group hampers the results. No information was available on the contraceptive consumption among the participants but one could assume it would yield an increase in fat mass or fat percentage.

6 Conclusion

On completion of the 12-week resistance training it seemed that the direction as well as the magnitude of change in the assessed variables differs between the normal-weight group and the obese group. In the normal-weight group all variables increased when baseline is compared with week-12 outcomes. In the obese group, change was in the negative, viz. all variables showed decreased values. Regarding the magnitude of change, the normal-weight group showed practically significant increases in compliance, FFM and RMR when the 12-week value is compared with the baseline. In the obese group practically significant changes (decrease) occurred in WC and BMI. It should also be noted that some significant changes occurred earlier in the training program. In the normal-weight group significant changes took place during week 4 (compliance and FFM), while in the obese group significant changes occurred in compliance, WC and FFM.

http://dx.doi.Org/10.4314/esa.v27i2.3

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M Swanepoel

GL Strydom *

Physical Activity and Recreation Research Focus Area

Faculty of Health Sciences

North-West University (Potchefstroom Campus)

P/Bag x 6001

Potchefstroom, 2520

South Africa

12262404@nwu.ac.za

Gert.Strydom@nwu.ac.za

* Corresponding author
Table 1: Sequence of the circuit program

Order   Body area          Exercise         Intensity   Volume   Rest

1       Chest              Peck Dec         60-65% of   3 x 15   30-60
                                            1-RM                   sec
2       Legs (anterior,    Leg press        60-65% of   3 x 15   30-60
          upper)                            1-RM                   sec
3       Upper back         Lats pull down   60-65% of   3 x 15   30-60
                                            1-RM                   sec
4       Legs (posterior,   Leg curls        60-65% of   3 x 15   30-60
          upper)                            1-RM                   sec
5       Shoulders          Seated press     60-65% of   3 x 15   30-60
                                            1-RM                   sec
6       Legs and           Abduction        60-65% of   3 x 15   30-60
          buttocks           machine        1-RM                   sec
7       Arms (anterior)    Bicep curls      60-65% of   3 x 15   30-60
                                            1-RM                   sec
8       Inner thighs       Adduction        60-65% of   3 x 15   30-60
                             machine        1-RM                   sec
9       Arms (posterior)   Triceps push     60-65% of   3 x 15   30-60
                             downs          1-RM                   sec
10      Lower back         Back             60-65% of   3 x 15   30-60
                             extensions     1-RM                   sec
                             machine
11      Legs (lower)       Seated calf      60-65% of   3 x 15   30-60
                             raises         1-RM                   sec
12      Abdominal          Tri-axial                    3 x 15   30-60
                             crunches                              sec

1-RM = One Repetition Maximum

Table 2: Descriptive statistics (means and standard deviation) and
effect sizes of the normal-weight and obese participants, following a
resistance training regime for 12 weeks.

              Normal-weight group
              Age = 27.8 ([+ or -]  3.8)

Period
              Baseline           4 weeks            8 weeks
              (n = 36)           (n = 21)           (n = 16)

Variable
Exercise                         9.42               10.56
sessions                         ([+ or -] 2.13)    ([+ or -] 2.92)
attended                                            d = 0.70
                                                    ([double dagger])
Mass          58.10              58.51              59.55
(kg)          ([+ or -] 6.78)    ([+ or -] 6.60)    ([+ or -] 4.46)
                                 d = 0.06           d = 0.20

BMI           21.35              21.51              22.00
(kg x         ([+ or -] 1.53)    ([+ or -] 1.79)    ([+ or -] 1.47)
[m.sup.-2])                      d = 0.03           d = 0.13

WC            68.66              68.78              69.11
(cm)          ([+ or -] 4.25)    ([+ or -] 4.31)    ([+ or -] 4.23)
                                 d = 0.02           d = 0.06

FM            17.10              16.21              16.94
(kg)          ([+ or -] 3.51)    ([+ or -] 4.07)    ([+ or -] 4.51)
                                 d = 0.08           d = 0.01
FFM           40.72              41.41              42.77
(kg)          ([+ or -] 4.28)    ([+ or -] 3.51)    ([+ or -] 3.27)
                                 d = 0.25           d = 0.55
                                                    ([double dagger])
RMR           4711.52            4767.00            4912.95
(kJ x         ([+ or -] 102.86)   ([+ or -] 108.40)   ([+ or -] 140.83)
[day.                            d = 0.10           d = 0.35
sup.-1])                                            ([double dagger])

              Normal-weight group
              Age = 27.8 ([+ or -] 3.8)

Period                             %
              12 weeks             Change
              (n = 12)             from
                                   baseline
Variable
Exercise      10.91
sessions      ([+ or -] 6.73)      [up arrow] 15.8
attended      d = 0.78t
              ([double dagger])
Mass          60.59
(kg)          ([+ or -] 5.26)      [up arrow] 4.3
              d = 0.40
              ([dagger])
BMI           22.04
(kg x         ([+ or -] 1.59)      [up arrow] 3.2
[m.sup.-2])   d = 0.14

WC            69.23
(cm)          ([+ or -] 4.67)      [up arrow] 0.8
              d = 0.07

FM            17.22
(kg)          ([+ or -] 4.21)      [up arrow] 0.7
              d = 0.01
FFM           43.90
(kg)          ([+ or -] 2.85)      [up arrow] 7.8
              d = 0.83
              ([double dagger])
RMR           5040.00
(kJ x         ([+ or -] 122.93)    [up arrow] 7.0
[day.         d = 0.58t
sup.-1])

              Obese group
              Age = 30.6 ([+ or -] 4.9)

Period
              Baseline           4 weeks             8 weeks
              (n = 41)           (n = 29)            (n = 20)

Variable
Exercise                         9.75                10.15
sessions                         ([+ or -] 1.81)     ([+ or -] 4.43)
attended                                             d = 0.40
                                                     ([dagger])
Mass          86.73              88.67               88.37
(kg)          ([+ or -] 16.40)    ([+ or -] 16.24)   ([+ or -] 18.22)
                                 d = 0.12            d = 0.09

BMI           32.99              31.46               32.83
(kg x         ([+ or -] 6.20)    ([+ or -] 6.30)    ([+ or -] 6.74)
[m.sup.-2])                      d = 0.31            d = 0.03
                                 ([dagger])
WC            89.44              86.85               88.03
(cm)          ([+ or -] 9.83)    ([+ or -] 9.84)     ([+ or -] 10.77)
                                 d = 0.32            d = 0.17
                                 ([dagger])
FM            39.24              36.83               40.10
(kg)          ([+ or -] 12.88)   ([+ or -] 14.20)    ([+ or -] 15.25)
                                 d = 0.22            d = 0.08
FFM           49.42              49.62               48.79
(kg)          ([+ or -] 4.43)     ([+ or -] 3.90)    ([+ or -] 5.35)
                                 d = 0.12            d = 0.32
                                                     ([dagger])
RMR           6011.38            5957.70             5908.14
(kJ x         ([+ or -] 93.87)   ([+ or -] 96.6)     ([+ or -] 125.96)
[day.                            d = 0.12            d = 0.18
sup.-1])
              Obese group
              Age = 30.6 ([+ or -] 4.9)

Period                           %                  p-value
              12 weeks           Change             (change
              (n = 20)           from               over
                                 baseline           time)
Variable
Exercise      8.56
sessions      ([+ or -] 4.84)     [down arrow] 9.3   0.270
attended      d = 0.55

Mass          83.49
(kg)          ([+ or -] 17.67)    [down arrow] 3.7   0.321
              d = 0.20

BMI           32.64
(kg x         ([+ or -] 6.69)     [down arrow] 1.1   0.857
[m.sup.-2])   d = 0.07

WC            86.85
(cm)          ([+ or -] 10.31)    [down arrow] 3.0   0.758
              d = 0.32
              ([dagger])
FM            38.35
(kg)          ([+ or -] 14.28)    [down arrow] 2.3   0.255
              d = 0.08
FFM           49.07
(kg)          ([+ or -] 4.70)     [down arrow] 0.7   0.107
              d = 0.06

RMR           5979.54
(kJ x         ([+ or -] 142.72)   [down arrow] 0.5   0.435
[day.         d = 0.06
sup.-1])

BMI = Body Mass Index; WC = Waist Circumference; FM = Fat Mass;
FFM  = Fat-Free Mass; RMR = Resting Metabolic Rate % change = Pre-Post
value/Pre-value; [dagger] = medium effect size [double dagger]  =
large effect size
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Author:Swanepoel, M.; Strydom, G.L.
Publication:Ergonomics SA
Article Type:Report
Date:Dec 1, 2015
Words:5759
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