Should Cardio Come Before, or After Resistance Training?
Traditionally, a complete training session is composed of a low-intensity cardiovascular warm-up, resistance training, and cardio training, followed by a cool down and stretching. This arrangement allows for an optimal stimulation of all physical qualities for people who exercise at the moderate frequency of 2 to 3 times a week. Many are wondering if they should perform their cardio at the beginning of their session, or at the end. Truth is, beginning a workout with a cardiovascular exercise that is too intense or lengthy has some drawbacks.
First, performing cardio at the beginning of the workout lowers the energy reserves of the only fuel available for resistance training. To simplify (because in reality, it is more complex), we could say that the human body uses two main sources of energy, that is carbohydrates (in the form of sugars in the blood, and muscular glycogen) and lipids (fats). Depending on the length and intensity of the cardio session, the organism can use both energy sources in variable proportions, but resistance training only uses carbohydrates in the form of glycogen (and also creatine phosphate). So, if we begin with cardio (especially if the intensity is relatively high), less carbohydrates will be available for resistance training, and the muscular work will then become less effective. On the contrary, if we begin with resistance training and use up part of our carbohydrates reserves, we will still have our lipids in stock to help us through our cardio session.
In second place, beginning with cardio can be detrimental to one of the main objectives of resistance training, which is the increase of muscular strength. To improve our muscular capacity in an optimal way, we should not be tired. If we want to lift serious charges and force our body to become stronger, we have to feel “well rested”. In very demanding and high-intensity sessions, the first part clearly harms the performance during the second part. For optimal results, it is recommended to separate these two types of training on two different days.
Finally, though less important, injury prevention is another argument indicating that it is better to begin with resistance training. Otherwise, our muscles having been slightly exhausted by our cardiovascular exercises, we run more risk of injury.
Despite all this, there is an important nuance to add here. It is not always necessary to follow very strict recommendations to reach our objectives, for example, in the case of a gradual weight loss or when getting back in shape. If you enjoy mixing up your sessions and this keeps you motivated, you can keep this habit. Still, the best solution is to question your trainer and check if the planning of your sessions is suitable to your objectives and physical condition.
By Mathieu Rousseau
– Costill, D., Wilmore, J. Physiologie du sport et de l’exercice (3e édition). Bruxelles : Éditions De Boeck Université, 2006.