Is Training Intensity the Key to Strength & Muscle Hypertrophy?

Strength training, performed on a regular basis, is an important tool in any training toolbox especially when the goal is to increase strength and muscle hypertrophy.

Looking at the Training Intensity or Volume Question

Research from the University of Central Florida, published in Physiological Reports, tested a group of 33 active, young men, who had a strength training background, to determine the best training variable for increasing strength and muscle hypertrophy.

The purpose of the study was to compare a moderate intensity, high-volume training program using short rest intervals to a program that used high-intensity, lower volume utilizing a longer rest interval in resistance-trained male individuals. Subjects were tested at the start and finish of the 8-week study. Among the many items tested, muscle strength, hypertrophy, and endocrine response were the main outcomes that the research group wanted to explore.

“It has been suggested that high volume, moderate-to-high intensity resistance exercise programs utilizing short rest intervals primarily target muscle hypertrophy with secondary strength increases (Baechle, 2008; Ratamess, 2009). Conversely, high-intensity, low-volume programs utilizing long rest intervals primarily target muscle strength increases with secondary improvements in muscle hypertrophy (Baechle, 2008; Ratamess, 2009). However, it has been hypothesized that muscle hypertrophy may increase substantially across a larger spectrum of intensity and volume combinations (Schroeder, 2013).”

Physiological Reports (2015)

Exercise Prescription Pinpoints Training Intensity

One group followed a high volume training plan (4 x 10–12 repetitions with ~70% of one repetition maximum (1-RM) with 1-minute rest intervals). The second group followed a high-intensity plan to prep for the study (4 x 3–5 repetitions with ~90% of 1RM with 3-minute rest intervals). Subjects were randomly placed in one of two groups for a 2-week preparatory training period prior to the study.

4-Day Exercise Prescription used in the study.

Day 1

Day 2

Day 3

Day 4

  • Back squats
  • Deadlift
  • Leg press
  • Lat pull down
  • Barbell bent-over row
  • Barbell biceps curl
  • Bench press
  • Incline bench press
  • Dumbbells fly
  • Seated shoulder press
  • Lateral dumbbell raise
  • Triceps extension
  • Barbell squat
  • Deadlift
  • Barbell lunge
  • Seated row
  • Dumbbell pull-over
  • Dumbbell bicep curl
  • Bench press
  • Incline bench press
  • Incline dumbbell fly
  • Seated shoulder press
  • Lateral dumbbell raise
  • Tricep extension

Research Study Findings

Study findings determined high-intensity (3–5 RM), low-volume strength training was the best option to stimulate strength gains and muscle hypertrophy. The high-intensity group used longer rest intervals (3-minutes) in their training sessions. Subjects, in group 2, used a moderate intensity, high-volume (10–12 RM) training program with shorter rest intervals (1-minute).

As a by-product of this research, Jefit developed a new strength training protocol called 4×5 Muscle Building (4-day) which is a great follow-up to Jefit’s 5×5 Split Routine (3-day). The emphasis should be placed on training intensity in both programs. Give this science-backed 4-day exercise prescription a try and let us know what you think. Stay Strong with Jefit.


Baechle, T., R. Earle, and M. Wathen. 2008. Essentials of strength training and conditioning. 3rd ed. Human Kinetics, Champaign, IL.

Ratamess, N. A., B. A. Alvar, T. K. Evetoch, T. J. Housh, W. B. Kibler, W. J. Kraemer, et al. 2009. American college of sports medicine position stand. Progression models in resistance training for healthy adults. Med. Sci. Sports Exerc. 41:687.

Schroeder, E. T., M. Villanueva, D. D. West, and S. M. Phillips. 2013. Are acute post-resistance exercise increases in testosterone, growth hormone, and IGF-1 necessary to stimulate skeletal muscle anabolism and hypertrophy? Med. Sci. Sports Exerc. 45:2044–2051.

Mangine, G.T., Hoffman, J.R., Townsend, J.R., et. al. The effects of training volume and intensity on improvements in muscular strength and size in resistance-trained men. Physiol Rep, 3 (8), 2015, e12472, doi: 10.14814/phy2.12472

Exercise Terminology is Important for Workout


There is so much information about working out and exercise terminology that it’s hard to keep things straight at times. It’s important to become more educated regarding this terminology in order to improve both the workout and training experience. Having a better understanding of the following terms will help in both of those areas.

Compound Set & Exercise are Exercise Terminology to Know

Compound sets use full body exercises to perform a series of sets using minimal or no rest. The same muscle group or opposing muscle groups can be worked this way. As the first muscle group recovers partially, a second area on the body can be worked. Training with this format allows for a more efficient workout. Many bodybuilders use this type of training model when trying to build muscle hypertrophy. A good example of a Jefit strength training workout that features compound sets is the Compound Strength Routine.

A compound exercise, or multi-joint exercise, is a full body movement like a Barbell Squat or Kettlebell One-Arm Clean. To perform one of these movements, multiple muscle groups need to perform together to execute a movement.


When you take a good look at exercise terminology and the history of supersets you’ll notice two distinct systems. One method involves several sets of agonists and antagonists muscle groups. An example of this is a Dumbbell Bicep Curl and Tricep Dip. A second type of superset can use one set of several different exercises working one specific area of the body like the chest. An example of this is one set of dumbbell Bench Press followed immediately by dumbbell Chest Fly and then Push-ups. Typically this types of superset uses 8-10 repetitions with each set of exercise with no rest between sets.

Ascending & Descending Pyramids

A strength training program can also utilize a pyramid method for program design. Any type of workout can benefit from a pyramid training method especially powerlifters. There are two options, performing sets where you progress from light to heavy weight, is an ascending pyramid. When sets of an exercise transition from a heavy to light weight, it’s considered a descending pyramid. The weight is typically light and starts with 10-12 repetitions and the weight gets heavier as the repetitions decrease until you reach one repetition.

Negative Repetitions

The lowering phase of a repetition is known as an eccentric contraction or negative phase. When this phase occurs, a muscle is actively lengthening (think Bicep Curl for a moment) so the weight can be slowly lowered in a controlled fashion. An individual can actually handle or control more resistance on the lowering phase of an exercise. Negative lifts require a spotter to help lift the weight up while the exerciser slowly lowers the weight. In terms of a resistance to use, around 105% to 110% of the concentric 1-RM should suffice. As an example, if someone has a Barbell Bicep Curl 1-RM of 135 pounds, the weight range to use would be about 140-150 lbs. The spotter would help left the weight upward while the exerciser slowly lowers the weight for the desired repetitions.

Circuit Training

Circuit training (CT) is a fast, efficient, way to exercise. CT consists of a series of strength training exercises performed one after the other with minimal rest. In regard to program design, 10-15 repetitions are used typically with 40% to 60% of 1-RM. There is a great deal of research showing the benefits of doing 8 to 20 weeks of circuit training. Increases in both maximal oxygen consumption (of 4-8%) and strength (7-32%) have been shown in men and women. An example of a Jefit circuit training program is Bodyweight Circuit Training.

The Jefit app is an award-winning workout planner & tracker app and a perfect built in coach that can assist you in putting these terms and more to good use – Stay Strong!