Under-trained instructors will take the bounce out of gym.
As the annual stampede to the gym begins after the festive binge, experts have warned fitness converts to chose their gym carefully.
Simon Harling, managing director of Elite Fitness said making the wrong choice could see people paying money for old rope.
His comments follow a survey commissioned by the Welsh Assembly Government which found that only 30% of gym managers were aware of the national qualifications for fitness staff.
Further undercover research by consumer organisation Which? found that although gyms say they employ qualified instructors, a third of them are unable to produce these qualifications.
Mr Harling said, 'A gym instructor should be an expert in fitness with an in-depth understanding of various medical conditions, much like dieticians and physiotherapists, who undergo years of training.
'We noticed that the vast majority of gyms and clubs have poorly educated and trained personal trainers - staff often have as little as one weekend's training in worst-case scenarios - yet new health clubs are opening up almost weekly across Wales.
'These are not acceptable standards for the fitness industry and the public should be aware of this as ultimately it is they who will be affected by a lack of trained professionals. We make sure our personal trainers have Masters degrees in Sports Science.
'We also require everyone who joins the gym to undergo the same comprehensive investigation, which begins with a general, and medical history screening developed in accordance with the American College of Sports Medicine guidelines.'
Elite Fitness, based on Fairwater Industrial Estate in Cardiff, is accredited with the British Association of Sport and Exercise Science and is the first of its kind in Wales to combine sports science laboratories, sports masseurs, physiotherapists and specialist trainers.
Mr Harling and Rob Ahmun, also of Elite Fitness, said it was important that new gym members set clearly identifiable goals and objectives when starting a fitness programme agreed between the participant and the exercise professional.
To get the most out of New Year training, goals should be 'Smart' - specific, measurable, achievable, realistic and time-based, such as the intention of losing 1kg body mass within two months.
The pair also believe that it is important that new members draw up an exercise plan which encourages enjoyment and exercising for health.
Incorporating a twice-weekly weight training session or similar into training schedules can help increase lean muscle mass and metabolic rate.
The American College of Sports Medicine also recommends that for the reduction of body fat, people should expend approximately 1,000 calories a week, rising to 2,000 calories.
Mr Ahmun said this could be achieved in a number of ways, including:
Taking part in large muscle group activities, such as walking, rowing, cycling or water aerobics;
Exercising at 60% to 75% of maximum heart rate;
Exercising three to five days a week;
Exercising for 40-60 minutes per session (or two sessions per day of 20-30 minutes), and
Putting emphasis on increasing duration rather than intensity.
The pair added, 'Remember 1kg of body fat is approximately equivalent to 7,700 kcal of stored energy. So results will not happen overnight.' You may lose the odd battle - just make sure that you win the war
WHEN starting a New Year exercise plan it is important to also devise a behaviour plan, according to Elite Fitness expert Simon Harling.
The behavioural plan should list patterns of eating and exercise that are beneficial to health and will lead to your goals and objectives being achieved.
There are other top tips to make the most of your New Year's resolution to get fit:
Join a class, find a training partner or ask an exercise professional for help if you find it hard to train on your own;
Limit your daily fat intake to 30% of your total daily calories, avoiding saturated fats, which are found mainly in animal and dairy products;
Eat regularly and often;
Try fruit or muesli bars as snacks and reduce your alcohol consumption as beer and other alcoholic drinks are calorie-dense and nutrient empty, and
Don't beat yourself up about the occasional chocolate bar. If the goal is to lose body mass over time, you may lose the odd battle but make sure you win the war.