We certainly all can think of an individual who stands by a cardio only exercise regimen as their normal exercise prescription. Maybe this form of cardio is distance running everyday or maybe it's a daily high intensity group cardio class. Either way, regardless of what this cardio looks like, it is preventing these individuals from reaching their full potential when it comes to transforming overall body composition. The reason being is that cardio only exercise regimens come with a number of limitations and also neglect the most important component of any exercise routine. Strength training.
Some of the biggest limitations of cardio only routines we should consider are the facts that they are hard on our joints, difficult to sustain long term, do not use a lot of muscles, and most importantly, do not have a huge impact on excess post-exercise oxygen consumption (EPOC). EPOC is very important when it comes to changing our body composition, as a study by Tucker et al. 2016 tells us the higher the exercise intensity, the longer in duration and magnitude the EPOC will be. Put simply, this means our bodies have to burn more calories post workout in order to recover. The problem with cardio only routines is that EPOC is not taken full advantage of.
Opposingly, high intensity strength training over a short time period is the best way to combat the limitation of EPOC we experience with only cardio. With full body strength training we are able to efficiently fatigue our entire bodies and as a result, we burn 5-10% more calories the following 24-72 hours in order to fully recover. In addition to this benefit of strength training, we also minimize the wear and tear on our joints and combat the other limitations of cardio only routines.
Tucker WJ, Angadi SS, Gaesser GA (2016) Excess postexercise oxygen consumption after high-intensity and sprint interval exercise, and continuous steady-state exercise. Journal of Strength and Conditioning Research 30(11):3090-3097.