Exercise v diet
Exercise v diet
This blog looks at the benefits of exercise versus diet for weight management and health.
People often go to the gym and seek advice from a personal trainer in order to lose weight. However, they may also investigate exercise and diet options in order to maintain their weight at a particular level or to gain weight and/or bulk.
The causes of obesity
Today, obesity has reached epidemic proportions. In the US, one of the causes is that people are consuming more energy than in the past. Centers for Disease Control and Prevention (CDC), which studied trends in intake of energy and macronutrients in the US between 1971 and 2000, found that average energy intake increased significantly between these years, from 2,450 kcal a day to 2,618 kcal a day.
In the UK, however, while energy and fat intake decreased between 1980 and 1995, the prevalence of obesity increased by more than 150%. This suggests a decline in energy expenditure – in other words, the UK population taken as an overall group was less active in 1995 than it was in 1980.
Recommendations for losing weight
The recommendations given to those wishing to lose weight are to increase the amount of exercise they do and to decrease calorie consumption. However, people do need to educate themselves on how to eat a healthy diet and what will be sustainable in the long run and it’s a good idea for fitness professionals to be well informed on these matters.
One option is for the personal trainer to ask their client to keep a food diary: a record of what they eat and when (see previous blog on Diet diaries: pros and cons).
Dieting is a major business and there are many weight-loss diets that claim to be quick fixes, as well as celebrity-endorsed diets. There are also companies selling supplements that claim to help weight loss.
Many of the so-called solutions are nothing more than a fad and often they involve limiting the types of food you eat, for example, low carb, high protein or fruit only. Some may bring short-term benefits but they tend not to be a long-term solution. In some cases, the downside to these diets can outweigh the benefits, as an individual may lose a few pounds but can find themselves deficient in the essential elements that the body needs to function.
As a result, it can be a challenge for personal trainers, fitness instructors and nutritionists, who are trying to encourage clients to eat healthily.
The importance of small steps
Those who are looking to get fit and improve their all-round diet – whether they are overweight, underweight or simply want to keep a balanced weight – are likely to be more successful if they make gradual changes.
If a personal trainer has a client who is eating a lot of high-fat foods and drinking sugary drinks, it would be a major leap to move to only eating salads and drinking water, and they are more likely to stick with smaller changes to their diet. This could be substituting a glass of water for a can of fizzy drink every day and then slowly introducing healthier food to replace high-fat or high-sugar foods in their diet.
Weight loss from changes to diet and behaviour
In 2003, H Lantz, M Peltonen, L Agren and J Torgerson undertook “A dietary and behavioural programme for the treatment of obesity. A 4-year clinical trial and a long-term post treatment follow-up.” The results of this have been reported in various journals, including the Journal of Internal Medicine (254(3), 2003) and the Health & Fitness Journal of the American College of Sports Medicine (ACSM) (Vol 8, No 5, 2004).
The study found that a group of obese women and men were able to maintain significant weight loss after a combination of a hypo-energetic diet and behavioural programme over four years. There was no surgery or medication for weight loss; the programme involved educating individuals about food and giving the participants cognitive therapy to encourage more positive lifestyle choices.
On average the participants lost 6kg to 8kg and those who completed the four-year programme maintained a 3kg weight loss for eight years after the programme ended.
How to get results from diet and exercise
For some people dieting only provides a short-term solution and they either return to their original weight or even put on more weight once they finish dieting. But if adults both reduce their energy input from food and increase energy burned through exercise, they are likely to have a better overall and long-term result.
Personal trainers will find that a client is more likely to be able to prevent weight gain with diet if they have access to some kind of behavioural support system. Local referral schemes often help participants by talking about the psychology behind our choices and why they may find it difficult to eat healthily.
Reasons for exercising
Although weight loss can be a good incentive for a client to want to work with a personal trainer, it’s worth remembering that a slim or thin person is not necessarily a healthy person and that there are many health benefits to exercise, even for those who don’t need or want to lose weight. As L Pescatello, SL Volpe, and N Clark state in an article: “Is Diet or Exercise More Effective?” (Health & Fitness Journal of the American College of Sports Medicine, Vol 8, No 5, 2004):
“Physical activity results in numerous health benefits with or without weight loss. These benefits include less abdominal fat, lower blood pressure, an improved blood lipid-lipoprotein profile, enhanced insulin action, and protection from cardiovascular and all-cause mortality even in the presence of overweight and obesity.”
Diet versus exercise
Various studies have found that the effects of diet and exercise are similar if the energy deficit imposed is similar.
However, a personal trainer may want to additionally advise a client that when they are only using diet to lose weight, they will see a loss of skeletal muscle, whereas when they lose weight through exercise, their skeletal muscle is preserved. This is because exercise stimulates the muscles and increases muscle tone and strength.
In conclusion, a personal trainer should advise clients that the best solution for weight loss is a combination of carefully planned diet and exercise.