|Do not misunderstand the results of the study at hand. It does not "proof that you don't have to use weights to make size gains" and it does not even suggest that "training without load works as effectively as training with loads for every muscle".|
To elucidate whether these hypotheses are accurate, Counts et al. recruited fifteen (6 men, 9 women) participants for a 6-week study (see Figure 1) ... untrained subjects.
Untrained? I know what you're thinking, but you got to start somewhere and to measure significant muscle gains in only 6 weeks, your subjects almost have to be untrained; even if this means that it is neither necessarily nor likely possible to transfer your results to trained individuals. It is thus well possible, that the NO LOAD conditions, the authors describe as follows, ...
"[t]he NO LOAD training condition is defined as voluntarily maximally contracting the muscle through the full range of motion without the use of an external load. During each NO LOAD training session, surface electromyography (EMG) electrodes were applied to the biceps to provide feedback to the participant and to help encourage greater activation during each repetition. The participants completed 4 sets of 20 repetitions with 30 seconds of rest between sets. This protocol was based off of pilot work performed in our laboratory which suggested that 4 sets of 20 repetitions should result in increases in both fatigue and muscle activation" (Counts. 2016).... will have smaller or even no effect at all on the muscle size of already trained individuals - and that would obviously be much in contrast to the tried-and-proven HIGH LOAD training in which the authors completed 4 sets of 8–12 repetitions with 90 s of rest between sets at 70% of their 1RM (weight was increased if more than 12 reps could be done).
|Figure 1: Study design outline. 1RM – one repetition maximum (Counts. 2016).|
- Contracting muscle through a full range of motion with no external load increases muscle size similar to high load training.
- High load training produced larger increases in 1RM strength & muscle endurance compared to contracting with no external load.
- Muscle growth can occur independent of the external load provided sufficient tension is produced by the muscle.
- Muscle strength is proportional to the load being used and the modality of exercise being performed (specificity)
|Figure 2: Mean muscle thickness from pre to post training at 50%,60% and 70% sites of the anterior (biceps) & posterior (triceps) upper arm (left) and individual differences in anterior muscle thickness (right | Counts. 2016).|
Eventually, the results of the study at hand, as intriguing as they may be, must thus be considered preliminary evidence in support of the mechanotransduction theory of muscle building and its implications, namely that no external load is necessary to stimulate the transcription factors that will eventually initiate the adaptive response to "no-weight lifting" (see Figure below)
- Counts, Brittany R., et al. "The acute and chronic effects of “NO LOAD” resistance training." Physiology & Behavior (2016).
- Rennie, Michael J., et al. "Control of the size of the human muscle mass." Annu. Rev. Physiol. 66 (2004): 799-828.