Since leaving a stressful job where I ate/slept at weird times I lost a couple of stone. I have lost even more now that I am cycling regularly, however, I had two neighbours pass comment yesterday when I was walking the dog on how much weight I had lost and sounding a bit concerned that I was too thin.
Is there a diminishing benefit for cycling if your weight goes too low?
Yes.
Essentially it is about trying to strike a balance between raw power and power to weight ratio, in order to excel at the type of cycling you choose.
If you get lighter and gain power. This is a perfect scenario, you gained all round!
If you get lighter and maintain power, this is the next best thing, you didn't give anything up (you maintained) and you gained in terms of power to weight ratio.
If you get lighter, the reality is you may lose some raw power, if the drop in weight is such that despite the loss in power causes an increase in your power to weight ratio, this is a reasonably good scenario in many cases (not in all, because some types of riding and terrain will benefit more from a higher raw power than a high power to weight ratio). You gave up raw power, but made a gain elsewhere.
If you get lighter and loose some raw power, if the drop in weight is cancelled out by the drop in power, such that your power to weight ratio remains the same, then this is none ideal, you have actually sacrificed raw power for no gain in terms of power to weight ratio, you gave something up and got nothing back.
If you get lighter and loose substantial amounts of power, the drop in weight won't cancel out the drop in raw power, both power to weight ratio and raw power figures will decline, if this happens, you really have mucked up!
The reason for declining power with losing weight is not always loss of muscle mass either, it can be attributed to many things, such as insufficient nutrition contributing to poor recovery.
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