Aerobic and resistance exercise do not mix… or do they? Contrary to popular belief, doing aerobic work around strength training can be beneficial. The timing depends on the goal:
If the goal is fat loss, do aerobic exercise after resistance exercise. Do the strength work while you’re fresh, then right after you’ve depleted your glucose stores, do aerobic work – you’ll tap into fat more readily that way. I talk about it in more detail in Lean and Mean.
If the goal is to gain muscle mass, do aerobic exercise 15 minutes before resistance exercise. Commencing resistance exercise in this manner with reduced glycogen stores and compromised function can induce sarcoplasmic hypertrophy.
If the goal is strength and power, wait 6 hours after resistance exercise to do aerobic exercise. As a restoration method, aerobic activity can improve recovery and boost the gains you make from strength training (see page 14 of Mass Explosion).
Of course, several variables will influence the training effect, such as modality (running will cause greater “muscle interference” than cycling), intensity, duration, and frequency, but the timing of aerobic exercise around resistance training is an important factor to consider.
For more information on concurrent training, check out page 178 of The Elite Trainer.