When designing training programs for strength or hypertrophy, a coach has to consider a number of variables including, exercise selection and volume and intensity distribution (set x rep schemes). The main objective of a program is to stimulate progress. Progress can be stimulated with simple progressive overload strategies where a small overload that exceeds previous training stimuli is prescribed. For example two successive three week waves may look something like this:
Week 1: 3×8 @135lbs
Week 2: 3×10 @ 135lbs
Week 3: 3×12 @ 135lbs
Week 4: 3×8 @145lbs
Week 5: 3×10 @145lbs
Week 6: 3×12 @145lbs
An alternative method thought to be a potent stimulus for progress is variation in exercise selection, or variation in intensity. This would involve frequently changing exercise for a given muscle group (Squat, Front Squat, Lunge, etc.) or intensity (frequent variation of set and rep schemes) to stimulate adaptation.
The effects of 4 different training methods on muscle hypertrophy of the quadriceps and maximal strength in the back squat were recently investigated by Fonseca et al. (2014). The researchers split 49 recreationally active but not resistance trained males into 1 of 5 groups:
Group 1: Constant Intensity, Constant Exercise (CICE)
– Squat exercise with 8rm
Group 2: Constant Intensity, Varied Exercise (CIVE)
– Squat, Deadlift, Lunge & Leg Press Exercises with 8rm
Group 3: Varied Intensity, Constant Exercise (VICE)
– Squat Exercise with 6-10RM
Group 4: Varied Intensity, Varied Exercise (VIVE)
– Squat, Deadlift, Lunge & Leg Press exercises with 6-10RM
Group 5: Control
– No training
Training took place twice per week over 12 weeks. Training volume was equated for all groups. Before and after the training intervention, muscle cross-sectional area was assessed for each quadriceps muscle via MRI as well as back squat 1 rep max.
The results showed that muscle cross-sectional area increases were not significantly different between the training groups (increases ranged from 9.3-12.2%). Interestingly, though overall muscle thickness was no different, the groups that varied exercises demonstrated hypertrophy in all 4 quadriceps muscles. The CICE group did not show hypertrophy in the vastus medialis or rectus femoris. The VICE group also did not show hypertropghy in the rectus femoris. The program that varied the exercise but not intensity (CIVE) was the most efficient at improving maximum strength for the squat while the varied intensity and varied exercise group showed the smallest improvements.
It would appear that varying exercises is beneficial for balanced muscle hypertrophy as well as increasing maximal strength based on the current results. Given that our interest pertains to developing athletes, it would be advisable to include a variety of exercises, both unilateral and bilateral and in various planes of motion. Athletes must be strong and efficient in various positions and angles. This is beneficial from both a performance and injury prevention standpoint. At the end of the day, keeping track of the training logs will help ensure continual progress. This way variation can be added when needed and is not random.
Fonseca, R. M., Roschel, H., Tricoli, V., de Souza, E. O., Wilson, J. M., Laurentino, G. C., … & Ugrinowitsch, C. (2014). Changes in exercises are more effective than in loading schemes to improve muscle strength. Journal of Strength and Conditioning Research, Ahead of Print.