When studies are designed to make sure that both groups are doing the same amount of total workload (sets x reps), muscle growth results are often similar. A similar occurrence can occur in protein powder and whey protein supplementation studies, in which one group consumes a whey protein isolate or whey protein concentrate after exercise gains more muscle. Was it because the group consuming the protein supplement after exercise caused more muscle growth? It could be that the protein supplement group consumed more total protein per day than the control or experimental group, which resulted in greater muscle growth.
ARTICLE OVERVIEW OF WELL DESIGNED RESEARCH STUDY
A well designed research study allow for similar exercise comparison with respect to volume.
A well-designed applied research studies allow for similar protein intakes when comparing the effects of a protein supplement.
IS IT THE TRAINING PRINCIPLE OR THE EXERCISE VOLUME?
It is common to see conflicting research studies regarding a specific training principle for building lean muscle. For example, a recent study on dropsets found greater increases in muscle hypertrophy in a specific thigh region than in the traditional training group. Adding drop sets can promote muscle growth, but if you examine the study, there were some key findings on why dropsets may have resulted in greater muscle growth.
Drop sets or running the rack is a method in which a person lifts a weight and, after fatigue, drops the weight and performs another set. Drop sets are a great way to fatigue working muscles, get great muscle pump (i.e., pump training), increase blood flow to a muscle, and add resistance exercise volume.
Examples of Unequal Exercise Volume
For example, if you are training on a leg extension machine, a lifter would train to failure, reduce the weight, and perform another set. Drop sets add volume for an exercising muscle group. Increasing blood flow results in greater expansion of the blood vessels, and an increase in nitric oxide can increase blood flow and nutrients to muscle cells and possibly increase muscle size.
The resistance training study lasted eight weeks, with the drop set protocol comprising a 5RM load to failure, reducing the load by 20% to failure again, then reducing the load by 10-15% to failure. The traditional strength protocol comprised 15RM to failure. At the end of eight weeks, although both had similar increases in leg muscle mass, drop sets resulted in a superior increase in the rectus femoris (front middle region of the thigh).
Upon analysis of the training volume, the drop set group resulted in a higher training volume. The greater exercise volume (i,e, high volume) with dropsets was suggested to enhance hypertrophy of the targeted rectus femoris compared to the traditional strength training group. More than likely, if the traditional group (i.e., control group) had done more sets to equal the training volume of the dropset group, increases in the muscle size would have been similar.
IS IT THE SPECIFIC EXERCISE PRINCIPLE OR MORE VOLUME DRIVING MUSCLE HYPERTROPHY?
Researchers do their best to standardize protocols when designing a well designed research study, but these issues sometimes happen. Sometimes research studies comparing the effects of two different resistance exercise protocols for muscle growth are unequal, and the sets or total workload for two workouts are different so that one group is doing more exercise.
The subjects did not gain muscle because they used some magic training principle. They grew more muscle because they did more muscle contractions during the exercise, resulting in greater muscle tension and muscle growth (i.e., muscle tissue hypertrophy). In the study mentioned above, the researchers suggested that the greater increase in rectus femoris growth was because of greater workout volume.