This is my first post here.And Here is one of the articles I wrote abou the topic of rep ranges and hypertrophy.
i couldn't link the references and graphs because I need more than 20 posts to do that. So if anyone can link the article, it would be great. My site is exercisebiology.com
Are low reps (1-6) better than high reps (8-12) for muscle growth?
BEGINNER | April 03 2010
The debate about whether high reps or low reps are better for muscle growth has been going forever. In fact, my thesis was on this exact question and I am yet to see any good evidence to favor either side.
Finally, a recent study which compared different repetition ranges sheds some light to the long- standing question.
Why are 8-12 reps better?
Bodybuilders: Bodybuilders always use the 8-12 rep range .Power lifters always use 1-3 repetition range.
Growth Hormone Increase: Number of studies show that 8-12 reps with short rest increases GH significantly compared to low reps.
Based on the above evidence, 8-12 reps is considered the standard recommendation for muscle growth or hypertrophy.
So why is there a debate?
Muscle Growth Studies: Surprisingly, the studies which looked at high reps and low reps show no significant difference in muscle growth.
GH ineffective: The GH hormone hypothesis of muscle growth doesn???t hold water anymore considering number of recent direct and indirect studies showing that exercise-induced increases in growth hormone (systemic hormones) do not help in muscle growth.
Greater Load: As reps decrease, the weight lifted increases. So theoretically greater the weight , greater the potential for growth.
But what about protein synthesis & rep range?
Your muscle increase in size because of an increase in protein synthesis. So the most simple question to ask is does high reps ( 8-12) show greater protein synthesis than low reps?.
Surprisingly, nobody ever bothered to look at protein synthesis and exercise intensity until this latest study.
The study compared different intensities ( 15%, 30% 1RM, 45%1RM, 60% 1RM, 90% 1RM) to see if there is a dose response relationship to weight lifted and protein synthesis. The subjects were beginners and the volume was kept similar in all groups.
What were the results of the study?
- And guess what, there was no significant difference in protein synthesis for the 60%, 75%, & 90% 1RM! Simply put, there was no significant difference for high reps and low reps.
- The study showed the same results for older individuals but the levels of protein synthesis were depressed which further confirms the above results.
- This study finally shows why studies which looked at outcome measures couldn???t find any significant difference in muscle growth with different rep ranges.
What about trained lifters?
In trained lifters, the curve may take either one of the shapes as shown below in the graph.
Practical Application
- There no magic in the 8-12 repetition range for muscle growth. If you are using a weight above 60% 1RM, you are getting the maximum level of your protein synthesis.
- There is no increase in protein synthesis as the weight goes up or the reps decrease. So 5RM is no better than a 10RM to increase protein synthesis.
- Theoretically, a high rep range would work the best for muscle growth considering there is less damage and nervous system fatigue compared to low reps.