Cardio or lift weights first in a training session?

Cardio and lifting weights are key components in any fitness program. But should you do cardio or lift weights first in a training session?

The simple answer is that it depends on your goals. If you want to focus more on muscle development and use cardio as a way to burn extra calories, lift weights first and then do cardio. Because as shown by the research, cardio before lifting fatigues you and reduces muscle performance [3]. The opposite of course holds true. If your main focus is endurance improvement, prioritize cardio first.

Now, if you want to maximally improve both your cardio and strength development, there is benefit in separating your cardio and lifting sessions.  A 2016 study found that separating your cardio and strength sessions by at least 6 hours results in improved strength gain [2]. So if you have the time, separating your cardio and strength sessions can help. A practical way to accomplish this is by doing cardio and lifting weights on separate days. Or perhaps even doing your weights in the morning and cardio in the evening, if you have experience with training 2 times a day.

📚 Scientific References:
1. LEVERITT, MICHAEL, and PETER J. ABERNETHY. “Acute effects of high-intensity endurance exercise on subsequent resistance activity.” The Journal of Strength & Conditioning Research 13.1 (1999): 47-51.

2. Tomiya, Shigeto, Naoki Kikuchi, and Koichi Nakazato. “Moderate intensity cycling exercise after upper extremity resistance training interferes response to muscle hypertrophy but not strength gains.” Journal of sports science & medicine 16.3 (2017): 391.