When we consider what the best exercise for weight loss is there are several factors we need to consider in order to choose, not only which exercise is best from a purely metabolic perspective but also other lifestyle factors, alongside an individual’s goals and abilities.
One of the biggest factors when choosing an exercise for weight loss is the time we have to actually exercise and how this fits in with an individual’s goals. For example, if we have a person who only has time to exercise for around 40 minutes per day in their lunch hour and is looking to build muscle and lose body fat, the obvious choice is to combine weight training to build muscle with a high intensity interval training (HIIT) cardio routine to boost their output in the shortest time possible. If someone is very short of time then they can also combine HIIT with functional, resistance training movements, to help build muscle and lose fat at the same time.
Obviously this is not optimal for muscle growth, but one of the advantages of HIIT training is that it does to a certain extent simulate aspects weight training and this has benefits of helping to protect muscle tissue and maintain a healthy metabolism especially if someone is also on a reduced calorie intake to help them lose weight, as without exercise muscle and in turn metabolism can be put at risk.
So does this mean that HIIT is the best exercise for fat loss? Well as with most things it depends on context, yes HIIT is great for getting in a fast and effective workout with high output but HIIT can only be sustained for very finite timeframes due to its large demand on the body, therefore steady state cardio which can be maintained often for longer periods and therefore overall the calorie ‘burn’ people are capable of is higher, but you don’t typically the same effects as HIIT for the potential to increase muscle mass at the same time and obviously, depending on the intensity of your steady state cardio can take much, much longer to perform.
Steady state cardio, especially very low intensity activities like walking are also more accessible to most people, especially those just starting out on their fitness journey whom may not be capable of performing this type of activity and even if they are it is very, very hard so can be off-putting for some people. In this situation it is probably better to start at lower intensity exercise and work up until a basic level of fitness has been achieved and a person is more conditioned and able to perform higher intensity training.
It might be expected then that for bodybuilders that they would want to perform HIIT training when they are trying to diet down to very low levels of body fat for a competition, for its muscle protective effects and it is something that through weight training they should be, to a certain extent conditioned to. Although some bodybuilders do use interval training as part of their cardio, a majority do however prefer to use steady state and there are a few reasons for this.
Firstly, if they are performing weight training sessions at high intensity, then they are already protecting their muscles through this activity and therefore cardio becomes more about increasing energy output to burn more fat.
Secondly, weight training can be hard enough on the body both physically and mentally as it is, and especially during dieting when energy levels can be low. Adding HIIT into the equation is going to put an already stressed body under more stress and potentially cause injury.
Thirdly, if we are talking at good level bodybuilders then the amount of muscle they are carrying means that any form of cardio can be very taxing on the cardiovascular system, even what superficially looks like moderate intensity exercise can be placing massive demands on the body if you’re 200+lbs of pure muscle!
In summary the best cardio exercise for weight loss for any individual, especially those who may not have taken part in regular exercise, should be something that they can sustain with their lifestyle and current fitness levels and the focus should be to progress exercise capacity gradually with time as fitness levels increase. This will ideally lead to exercise which contains elements of both steady state and high intensity training to maximise weight loss and encourage muscle building and positive metabolic effects.
