What is the optimal way to gain muscle strength?
How often should the muscle be trained? Should you focus on eccentric or concentric movement? Single arm curl or barbell curl? Does volume or intensity make a difference? We answer these questions through research.
As physio‘s there isn’t often a clear number of days a patient should train a particular muscle every week, as it can depend of factors such pain levels, accessibility to equipment, patient’s recovery time post training etc. However as a general guideline we turn to research by Thomas and Burns (2016).
19 healthy individuals were assigned to high frequency training group (HFT) or low frequency training group (LFT). HFT trained each muscle group 3 times per week, where LFT trained each muscle group once per week (*note: LFT performed 2 exercises for the same muscle)
The results: % of improvement after 8 weeks for
HFT on lean mass increase = 1.9%, Hack squat 1 repetition max (RM) weight = 21%, Chest press 1 RM = 11%
LFT on lean mass increase = 2.0%, Hack squat 1RM weight = 24%, Chest Press 1RM = 7%
Overall comment: minimal difference between training 3 times per week or once per week. (*note participants were healthy individuals without injury which often isn’t the case in clinic)
Concentric Vs Eccentric
Concentric is the movement when muscle is shortened during resistance. Eccentric is when the muscle is lengthened during resistance. A review by Roig and colleagues in 2009 looked at 20 studies to see which whether concentric or eccentric movement is better to gain strength.
The results: Eccentric training showed greater increase in muscle strength and muscle mass!
Single side or both at the same time?
When training to increase muscle strength would you train with both limbs at the same time or just one side at a time? It is important to consider at this point a term coined “Bilateral Deficit” which is when “the sum of torque (force) generated by each limb (individually) in the unilateral condition is greater than that generated by both limbs simultaneously”. Meaning your maximal single arm bicep curl is 15 kgs but when you curl with both arms you can only lift 25 kgs, when ideally it should makes sense to lift 30 kgs. One explanation is due to limited signals your brain can provide to the muscles at one time.
The results: Research done by Costa (2015) showed you’ll be able to lift approximately 11% heavier if its only single side but the total number of repetitions you lift will be lower compared to lifting with both sides. So for efficiency to target specific muscles perform single side only.
Volume or intensity?
Should you do more repetitions or just lift heavier to increase muscle strength?
A study by Magine (2015) demonstrated Group A that lifted more repetitions at 70% weight maximal increased muscle size by 2.2% after 8 weeks. Whereas the Group B that lifted heavier at 90% weight maximal increased muscle size by 5.2%.
The results: Intensity is key!
So what does this all mean?
In an ideal situation optimal parameters to gain muscle is training the muscles at least once per week with 2 exercises, single side, focusing on eccentric control with 4 sets of 3 – 5 repetitions, 2-3 minutes rest at 90% maximal weight (if able).