There are a number of key elements to achieving any weight management goals. The major two are correct nutrition and relevant exercise. Weight loss is achieved by consuming fewer calories than your body uses and weight gain is achieved by consuming a greater number of calories than your body uses, but what role does exercise play?



For weight loss, the primary purpose of exercise is widely assumed to be to burn calories, but are we able to get greater benefits from our exercise?

The answer to this is YES! The type of training you do can improve your body’s ability to burn fat. The human body can only burn fat when both carbohydrates and oxygen are present and so if you are aiming to lose weight, you need to encourage your body to store carbohydrates (in the muscles) and use oxygen more effectively. This is an excellent argument for why low carbohydrate diets are not ideal, because if there are no carbohydrates present in your body, then lean muscle mass is broken down to replace them.

In order to promote the adaptations discussed, your cardiovascular exercise should be done at a relatively high intensity (at lease 70% of your maximum heart rate - providing you have a reasonable cardiovascular fitness base to begin with!). This will promote an increase in the number of mitochondria within the muscles, enabling greater uptake and utilisation of oxygen.

For fat loss, resistance exercises should be done with repetition ranges of 15 and above, as this will improve the endurance capacity of the muscle. The muscle will once again produce greater numbers of mitochondria in order to reduce lactic acid production, hence improving the muscles ability to use oxygen.

For weight gain, the purpose of exercise is to ensure that the mass gained is lean tissue mass and not fat mass, so how is this reflected in the type of exercises performed?

Cardiovascular exercise should be done at a lower intensity, with the objective being to raise the body’s core temperature and prepare the joints and muscles for exercise, without burning excessive quantities of calories.

Resistance exercises should be performed with repetition ranges between 8 and 12. This is the ideal number of repetitions to promote muscular hypertrophy (muscle growth). In addition, when trying to add mass to your frame, compound exercises will activate larger quantities of muscle fibres, encouraging growth. A compound exercise involves movement at many joints, engaging many muscle groups.

In summary, the type of training we do can encourage adaptations within our active body tissue. These adaptations enable our body to function in a way that is in keeping with our goals.

Although our diet may determine whether we lose or gain weight, our choice of training methods will define the way our body produces and manages energy at rest, as well as during exercise. Even if someone were to train for 5 hours per week, there would still be 163 hours in the week when they were not training. Therefore it makes more sense to encourage your body to adapt in a way that it will function in keeping with your goals during rest, rather than purely concentrating on the direct effect of your training.