Aerobic exercise, also known as cardiovascular exercise – or cardio – refers to an activity in which you work consistently at a moderate intensity for an extended period of time. Running, cycling, cross-training, rowing, skipping, swimming, dancing and skiing are just some of an almost endless list of cardiovascular exercises, but which one is best for you? In this article I will try to uncover the different motivations for doing cardio in the first place, and attempt to identify which type offers the most benefit. The first step is to take a closer look at the individual, or more specifically what he or she wishes to achieve from such a workout.
Aims of the individual
People perform regular aerobic exercise for a variety of reasons. They may wish to lose weight, increase general fitness or improve sporting performance. In order to obtain some kind of specific goal, such as beating your 2000m time on the rower or improving your cross-country stamina, we need to look at a principle known as ‘specificity’. This principle states that to improve your performance in a specific exercise you should invest the majority of your time practising that exercise. If your aim is to increase your running endurance, for example, limited benefit will be gained by doing lots of cycling.
For life goals such as increasing general fitness or losing weight, the answer isn’t always as obvious. With these goals, individuals are often overwhelmed by the wide choice of cardio equipment available in gyms, many of which mimic real life activities such as running and cycling, whilst others have a completely original way of exerting the body (e.g. cross-trainer and wave machine).
Many articles exist that promote a particular piece of equipment for its unique capacity to work the muscles in ways that none other does. The rowing machine, for example, is said to be one of the best cardiovascular workouts because very few exercise machines use as many muscle groups through such a large range of motion. Personally, I am a keen fan of the rower because of these benefits but that does not necessarily make it the world’s best exercise.
Level of exertion
The rower, as with any mode of exercise, relies on how much effort the individual puts into it. Strapping your feet in and simply going through the motions is unlikely to increase the heart rate to any significant level and will lead to few results. Swimming is another example of ‘you get out what you put in’, as it is relatively easy to stay afloat and requires little additional effort to generate movement. What the body needs, whether you are looking to burn calories or improve endurance, is to be worked hard enough and for long enough (at least 20-30 mins) to cause significant ‘physiological changes’ to take place. In this case the physiological changes refer to a rise in heart rate (about 70-80% of its maximum), oxygen delivery to the muscles, and an effect that leaves the individual feeling warm and out of breath.
With reference to weight loss, working at an intensity that feels easy does not require much energy so will not burn as many calories, and this will apply whether you are walking, running, skipping or playing water polo. Similarly, improvements in stamina will only be seen if enough of strain is put on the body that forces it to adapt to the demands placed on it.
Variety and enjoyment
We have established that branding an exercise ‘superior’ in terms of its aerobic benefit becomes almost irrelevant if the level of exertion is not as high as it should be. However, some sources would still hold that one form of cardiovascular exercise is more physically demanding than another, and will be more beneficial. Although some exercises are more muscularly demanding at high intensities (like rowing and swimming), my response would be that no single exercise is the way forward, and that it very much depends on the individual. Also some exercises have inherent risks, such as placing high impact on the joints. Running involves impact which can cause problems for people with joint conditions. However this same impact helps promote bone density which fights against osteoporosis.
Performing any one exercise regularly and at high intensities is likely to provide results but two things will inevitably happen. Firstly your body will learn to adapt to the exercise by becoming more energy efficient and will not respond to it as readily as it did when you first started. This process of becoming gradually accustomed to an exercise programme is known as ‘plateau-ing’. More importantly the risk of boredom without variety and challenges could lead to you giving up. The easy solution here is to mix up your exercises. The more variety in an exercise programme (and this is true of exercise across the board, not just cardiovascular) the harder your body will have to work to meet the different demands made on it. Similarly, a variety of different activities will help you overcome boredom by keeping your exercise routine more interesting and enjoyable. Variety also helps to avoid the same stresses being placed in the same way on the same joints and muscles, thus reducing injury risk.
Lastly, but certainly not least, everyone is different. In the same way that not everyone enjoys the same types of music, some people are more responsive to certain exercises than others. I think a common mistake in the exercise world is to ignore this natural instinct, and by plugging away at exercises recommended to you but that you don’t enjoy, you are less likely to see long-term results.
When selecting an aerobic exercise you must first establish what you are trying to achieve. For specific endurance goals, such as running a marathon, you will benefit most effectively from practising that exercise. For general ‘life’ goals, such as losing weight, you are more likely to get results by doing something different each time you train, and in my experience the exercises that you get the most out of are the ones you enjoy. So what is the best aerobic exercise? Either the one that gets you quickest to a specific training goal, or the one(s) that are the most fun.