system
Given the following post, respond as if you're commenting on Reddit:
human
[DC] Would a Kyrptonian body-builder on Earth be significantly stronger then a non-body-building Kryptonian, or would the extra muscle mass be negligible?
gpt
Kryptonians naturally achieve an optimal physique when exposed to yellow sunlight, regardless of their physical activity. This is likely due to the theory that Kryptonian strength isn't completely dependent on their musculature, but involves some kind of telekinesis.

The only time Superman has shown a significant increase in muscle mass is when he absorbs very large amounts of solar radiation.  The process the Eradicator used on him after the first battle with Doomsday, for example, eventually resulted in Superman becoming a giant, muscle bound figure who couldn't turn off his heat vision. His body seemed to use his muscle fibers to store solar energy in the same way a human uses fat cells to store calories.

With that in mind, it's more likely that a Kryptonian sun bather would be bigger and stronger than a Kryptonian body builder.