Maximizing Muscle Growth

Preface

The red advice is based on meta-analyses or literature reviews.

At The Gym

  • Untrained people should work out 3 or more days per week. Trained people can get away with 2. dose response for strength development
  • You should perform about 4 sets for each exercise dose response for strength development. Each set causes 40% as much growth as the previous Single vs. multiple sets.
  • Resting 3 minutes between sets promotes more growth than shorter durations rest periods.
  • As long as you spend less than 10 seconds, it doesn't matter how long each rep takes repetition duration.
  • There's no reason to train to failure repetition failure.
  • Novices should lift as many reps as they can while lifting 60% of their max, while trained lifters should lift 80% dose response for strength development.
  • Trained lifters should lift as many reps as they can while lifting 85% of their max Maximizing strength development in athletes.

In the Kitchen

  • Protein up to 1.6 grams per kg of body weight per day improve muscle gains protein supplementation - that's about double the 0.8 recommended for the general population. A literature review recommends higher levels for people losing weight: between 2.3 and 3.1 dietary protein during caloric restriction g/kg/d.
  • Protein supplements work Protein supplementation, especially whey advantage whey,
  • Consuming more than 30g of protein in a meal yields no benefits, so you have to split your protein consumption throughout the day moderate serving of high-quality protein.
  • Consuming protein around the time of your workout has no effect on muscle growth except insofar as it may boost your total protein consumption protein timing.
  • You should definitely take creatine supplements, which have been found to increase muscle mass by something like a sixth of a pound per week among older adults. The only side-effects found were minor gastrointestinal issues creatine supplementation.

Creatine Dosage

I couldn't find any meta-analyses on the optimal creatine dosage so I decided to take a look at the data on my own. I looked at the creatine meta-analysis creatine supplementation and assumed the average American weight of ~182lb to convert between studies using creatine in g vs. g/kg. Then I constructed a scatter plot of the effect size on lean body mass (relative to the control group) after adding a little bit of noise for illustrative purposes. Unfortunately, the chart isn't very illuminating:

The charts representing the effect of creatine on chest press and leg press are similarly unhelpful.

Next, I tried dividing the studies into low-creatine (< 5.8 g/d) and high-creatine (>8.2 g/d). The average effect size in the high-creatine was 0.23 higher than in the low-creatine group. However, the p-value was fairly high (p=0.26) and this difference represents just a 16% increase in effect size, suggesting that the first ~5 g/d of creatine represent most (if not all) of the gains.

This analysis has two major problems, however. The first is high error bars due to small sample sizes and noisy muscle growth. The second is that there just aren't that many studies on the effect of very high creatine consumption on muscle growth (just 2 where more than 20 g/d was consumed).

Both these problems are mitigated by examining chest press strength gains instead:

Here, we actually find a negative difference between low and high creatine consumption, but p=0.4, so really the finding is just "no effect".

In short, there's clear evidence that non-zero creatine consumption promotes muscle growth. We have no reason to think more than 5 g/d helps at all, and for all we know the point of diminishing returns occurs far below that.

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Works Referenced