As part of our Biohacking Masterclass Series, we will explore a number of different techniques and practices to improve your daily performance. This series will range from obvious subjects like exercise and nutrition to fringe subjects like breathing techniques and sleep hygiene. Consult your physician before implementing any of these topics. We are not your physician.
This article is Part 2 of our research breakdown on training for strength and hypertrophy. If you haven’t read our breakdown on the optimal repetition and set schemes, read this 6 minute article first. If you’ve already gotten that one covered, you are ~5 minutes from reaching ‘expert’ status in training for greater size and force output.
To recap: in studies evaluating higher volume, lower load (lower weight) rep schemes compared to those with lower volume, higher load, researchers found that the powerlifting-style lower volume (<6 reps), higher load resistance training (HLRT) resulted in greater strength AND size gains than those seen in bodybuilding-style higher volume, lower load resistance training (LLRT). [1,2]
While lower rep schemes are a great starting place, blasting through a HLRT workout will lead to poor form, diminished recovery, and lower volume over the course of a workout. Optimal strength training requires another consideration: timing of sets and rest.
Contrary to what you might see in the gym, short rest periods are the enemy of optimizing your strength and size gains. While metabolic stress (the ‘burning’ sensation after an ‘AMRAP’ set) is one sign of hypertrophic stimulus, it limits the amount of quality work you can do in a given training session.
Instead, several studies have shown that longer rest periods lead to considerably better performance and results over a given training timeline. In a study evaluating 3 minute rest periods against shorter 1 minute rest periods, longer rest led to statistically significant strength gains and increased muscle size. For example, researchers found long rest periods led to a 7% increase in tricep thickness (vs. short rest increase of 0.5%), a 13.3% increase in quad thickness (vs. short rest increase of 6.9%, a 15.2% increase in 1RM back squat (vs. short rest increase of 7.6%), and a 12.7% increase in 1RM bench press (vs. short rest of 4.1%). Each of the study participants were held to an otherwise identical resistance training program. 
A 2009 review supports these findings: “[In] terms of chronic adaptations, resting 3-5 minutes between sets produced greater increases in absolute strength, due to higher intensities and volumes of training. Similarly, higher levels of muscular power were demonstrated over multiple sets with 3 or 5 minutes versus 1 minute of rest between sets.” 
When you’re after strength and size gains in the weight room, don’t confuse your sweat, burn, high heart rate for optimal work. Instead, focus on performing the highest quality reps over your given set schemes at a higher load. Many athletes in programs like this will spend well over an hour working one compound lift (bench, deadlifts, squats). This focus on quality will return a higher quantity of reps over a longer workout.
We will implement a HLRT-style program with at least 5 minutes of rest between sets. Often, we will get closer to 8 minutes with an emphasis on high-quality performance during sets.
Do you need to use 3-5 minutes with every exercise?
Not necessarily. Depending on the extent of multi-joint involvement, you may get away with shorter rest intervals. If you are performing a single-joint (i.e. isolation) exercise like a front raise or bicep curl, studies have shown a 2 minute rest may be sufficient. Multi-joint (i.e. compound) lifts like a bench press, back squat, or deadlift return better results with longer rest periods. 
We will typically follow our compound exercises with some targeted isolation exercises. These single-joint lifts will often be supersetted in pairs where rest periods are much shorter and muscle groups are different. For example, bicep curls can be performed immediately after triceps extensions.
- Schoenfeld, Brad J The Mechanisms of Muscle Hypertrophy and Their Application to Resistance Training, Journal of Strength and Conditioning Research: October 2010 - Volume 24 - Issue 10 - p 2857-2872
- Grgic J, Schoenfeld BJ. Are the Hypertrophic Adaptations to High and Low-Load Resistance Training Muscle Fiber Type Specific?. Front Physiol. 2018;9:402. Published 2018 Apr 18. doi:10.3389/fphys.2018.00402
- Schoenfeld, Brad J.1; Pope, Zachary K.2; Benik, Franklin M.2; Hester, Garrett M.2; Sellers, John2; Nooner, Josh L.2; Schnaiter, Jessica A.2; Bond-Williams, Katherine E.2; Carter, Adrian S.2; Ross, Corbin L.2; Just, Brandon L.2; Henselmans, Menno3; Krieger, James W.4 Longer Interset Rest Periods Enhance Muscle Strength and Hypertrophy in Resistance-Trained Men, Journal of Strength and Conditioning Research: July 2016 - Volume 30 - Issue 7 - p 1805-1812
- Senna, Gilmar W.; Willardson, Jeffrey M.; Scudese, Estevão; Simão, Roberto; Queiroz, Cristiano; Avelar, Raoni; Martin Dantas, Estélio H. Effect of Different Interset Rest Intervals on Performance of Single and Multijoint Exercises With Near-Maximal Loads, Journal of Strength and Conditioning Research: March 2016 - Volume 30 - Issue 3 - p 710-716
- Freitas de Salles, B., Simão, R., Miranda, F. et al. Rest Interval between Sets in Strength Training. Sports Med 39, 765–777 (2009).