Is lifting Heavy Weights a necessity for improving Strength and Muscle Growth?

If you have ever been to a gym at some point you have heard people preach about how lifting heavy weights is the only way of getting stronger and building muscle. Is this actually true?

We will be answering the following question.

• What are the effects of high vs low load on strength and muscle growth?

There are people out there who put that question to the test ,compiled a total of 21 studies and reported their finding.

These studies had to meet a certain criterion. They all had to include

1) Experimental trial including both low load <60% of 1 rm, and high load >60% of 1 rm training

2) All sets needed to be performed to momentary muscular failure

3) Needed to include at least one method of assessing changes in muscle mass and strength

4) Testing protocol had to be at least 6 weeks long

5) Subjects needed to be healthy, with no medical conditions or injuries, to not affect their ability to train

Let us go over the finding and how we can interpret the information

Findings for strength:

Before you start scratching your head and wonder “what am I looking at here”. Let me simply discuss the picture above.

On the far-left side of the chart there are 14 studies with the individual or group of people that performed the test their name and year. Over to the right there are the effect size of the study which shows how meaningful the relationship between variables are, or the difference between groups . As in a large effect size has meaningful significance, and a small one has limited significance. For reference 0.2 would be a low effect size where an 0.8 to 1.0 would be meaningful one.

With all this information how can we interpret the previous image. What this is telling us is that training with heavy/high loads will lead to greater adaptations or gains in strength. Ie: lift heavy to get stronger.

Findings for hypertrophy or muscle growth:

This picture is interpreted the same as the previous one

These ten studies are showing us that there were no statistically significant difference between high vs low loads. However, one can make the argument that training with higher loads will lead to greater adaptations on muscle growth.

Applications:

Now that you survived all those charts and numbers. How does this apply to you and how to apply it into your gym routine. Let’s get the easy one out of the way, it is quite apparent that training with heavy loads is the best way to get stronger, especially the more experienced the lifter is the more time he/she needs to spend at those higher intensities. With that said a reminder needs to be in place, the athlete shouldn’t just lift heavy forever (>60%), there are times where the body will need to recover, and recovery strategies will need to be implemented. A drop in volume (sets and reps) primarily needs to occur and adequate strategic drops in intensity as well.

Pertaining to muscle growth, we must think about what is practical. According to this analysis there weren’t statistically significant differences between high vs low loads. However, in the real world its not practical to squat or dead lift 5 sets of 20 reps with a barbell, where the potential for decay in technique and injury can be high, also it would be quite psychologically exhausting to get really excited about such workout. Instead, a rep scheme of 5 sets of 8-10 is easier to digest. A recommendation would be to leave those high rep schemes towards more isolating machine-based exercises, where it can be executed safely and enjoy that “pump” sensation.

Reference : MASS volume 1 , issue 7