The Claim
Resistance exercise performed to task failure results in comparable glycogen depletion in both type I and type II muscle fibers, regardless of whether the load is heavy or light, indicating that both fiber types are fully recruited under fatiguing conditions.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
When muscle fatigue is reached during resistance exercise, both slow-twitch and fast-twitch muscle fibers use up the same amount of glycogen, whether the weight is heavy or light.
See the scientific wording
Resistance exercise performed to task failure results in comparable glycogen depletion in both type I and type II muscle fibers, regardless of whether the load is heavy or light, indicating that both fiber types are fully recruited under fatiguing conditions.
When you lift weights until you can't do another rep, your muscles run out of energy in the slow-twitch fibers first, so your body turns on the fast-twitch fibers to keep going. Both fiber types use up all their stored sugar, no matter if the weight is light or heavy, because you pushed until complete fatigue.
What the research says
1 studyWhen you lift weights until you can't do another rep, your body has to use all your muscle fibers—even the fast-twitch ones usually used for heavy lifting—no matter if the weight is light or heavy. The study shows both types of fibers run out of energy the same way when you push to failure.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.