REST TIME FOR MUSCLE GROWTH FULL

If you match load instead of effort, you can actually bias a study the opposite way. In this way, you could argue that matching for effort and volume “biases” long rest periods to be better because in reality, a group resting for a much shorter period between sets could accomplish more total sets in the real world, and perhaps end up doing more volume in the same time period.īut there are other ways researchers can match groups. However, if you were to rest a shorter period, but do additional sets to “make up” for lost volume due to incomplete rest, you can get on equal footing with a longer rest protocol as shown in a study by Ahtiainen and colleagues.

Reason being, the short rest group had to decrease the weight more than the longer rest group to fail in the target rep range due to more cumulative fatigue set-to-set. Thus, number of sets were matched, effort per set was matched, but volume load (total tonnage lifted) was lower in the short rest group. In this case, load was adjusted each set to ensure failure occurred in the 8-12 rep range each set.

REST TIME FOR MUSCLE GROWTH FULL

This is the principal hypothesis why shorter rest periods are thought to be worse for hypertrophy: less total mechanical stimulus (tension/load and volume of tension).įor example, Schoenfeld and colleagues compared two 3 day/wk full body protocols using either 1 min or 3 min rest periods with both groups doing 3 sets to failure on 7 exercises: squat, leg press, leg extension, bench, OHP, lat pulldown and cable row. When you rest for a short period between sets, and get incomplete recovery, you’ll hit failure with fewer reps or have to reduce the load to perform the same number of reps. Most studies have participants train to failure. However, “matched for volume and effort” is an important caveat. As the question indicates, most studies show that when matched for volume and effort, training protocols with longer rest periods produce similar or sometimes greater hypertrophy than those with shorter rest periods. With the background understood, let’s discuss the direct data on longer and shorter rest periods and hypertrophy. High work:rest ratio resistance training that increases GH (and lactate) can produce hypertrophy, but is the GH response necessarily the primary causative factor? Runners performing 30s sprints experience robust increases in GH (and lactate which are strongly correlated) but, would you expect an entire 5x5RM full body training session with 3 minute rest intervals to produce less hypertrophy than a single 30s sprint, just because it resulted in a fraction of the GH response (1-5 vs 8-24 µg/L)? Obviously not! Indeed, a recent review examining this relationship concluded acute hormonal responses to exercise are not directly correlated with muscle growth per se. Given the metabolic role of GH, it’s unsurprising that GH release is enhanced under acidic conditions and that lactate and GH responses to exercise are significantly correlated. Higher blood lactate levels create more acidic conditions. Training with a high work:rest ratio creates a large, immediate demand for energy and increases lactate. However, despite its name, “growth hormone” does not just impact growth. Originally, short rest periods were promoted as superior by the scientific community for hypertrophy based on data showing high volume training paired with restricted rest (the highest work:rest ratio) produced the largest acute growth hormone (GH) response. To do this, we’ll need to understand how we got to the modern concept of resting longer being superior for hypertrophy, from where exercise science used to be – believe it or not old recommendations were to rest for shorter periods for hypertrophy – and also discuss the nature of fatigue. We’ll dive into this, and you’ll finish this blog with a nuanced understanding of rest periods, fatigue, their impact on hypertrophy, and ultimately, understand more than “short rest periods are bad”.

That said, just because this isn’t fully understood, doesn’t mean there isn’t a hypothesis consistent with the data. That’s exciting, as it means there’s more to learn about the nature of fatigue and hypertrophy. I’ve discussed this with other researchers (shout out to James Krieger much of this is based on our discussion in Norway a few years back and his writings) without coming to a definitive answer. We received a great question recently: “How do we reconcile studies where rest-pause and drop sets produce similar hypertrophy as straight sets, and data showing short rest periods produce less hypertrophy than longer?”

Rest time for muscle growth