How much muscle do I need for optimal strength to weight ratio?

Question

Ever since I started getting into powerlifting at age 16, I've been weighing 100kg+ at 192cm. Lately I've burned a ton of fat by playing badminton and my bodyweight is now around 90kg with 7%bf. However I'm trying to get to around 80-85kg now since I notice most badminton pros my height weigh between 70-82. This means I have to cut some muscle mass. Which makes me wonder if anyone has some nice information or articles about how much muscle mass do you need relative to your height and bodytype in order to maximize strength to weight ratio?

(assumptions)

1. Let's assume the athlete already has an optimal bodyfat% so they can't cut fat anymore
2. Let's also assume that the neurological efficiency of the muscle mass is very high and the strength of the athlete's muscle is close to powerlifting records for that weight class.

Here's a chart I made based on some existing drugfree powerlifting records: http://puu.sh/hZNC8/48a8ccfec5.png We can see that the general trend seems to be the lighter the athlete, the higher their strength to weight ratio. However these records involve different people with different body compositions. The lighter strength athletes will also likely be shorter people. So this doesn't really help me that much because what I want to know is how having more or less muscle mass would affect the strength to weight ratio of people with the same body composition

Answer 1

If we're controlling for bodyfat and muscle strength per unit size, then the only downside to adding as much muscle as possible is the square-cube law. (And the limits of human digestive capability, I suppose.) This is, of course, absurd: no athlete (even in a non-weight-class sport) simply chooses to continue adding muscle mass ad infinitum. The disconnect between reality and the answer to your question is due to A) other factors and B) the assumptions you explicitly included: that body fat and muscular efficiency are held constant.

Why don't we see 100kg gymnasts? Because athletes need to balance sport-specific training with strength and conditioning training as well as rest. Because there is a limit to an athlete's eating capacity. Because big people (and their coaches) find gymnastics difficult even at the novice level and don't start training. Another key element is because holding body fat and neuromuscular efficiency constant while gaining or losing weight is really hard.

For instance, if we take X pounds of lifter with powerlifter-efficiency muscle, and adding muscle doesn't require adding fat or lowering neuromuscular efficiency, then that lifter wants to add infinity muscle. The relevant variables are held constant.

More relevant to your situation is the fact that almost no one's neuromuscular efficiency or body fat percentage are ideal. Nearly every athlete could sport much less muscle and still be as strong as they are, and similarly most athletes have fat to lose. But manipulating those variables takes a lot of specialized training that usually has less return on investment than simply training their sport and doing basic strength and conditioning. Assuming that one can magically teleport to a different physical milieu doesn't help with deciding on training choices in the here-and-now.