Temperature can have a big effect on how accurately people judge their reps in reserve during exercise. Reps in reserve means how many more reps someone thinks they can do before reaching muscle failure. When the temperature is too hot or too cold, it can change how the body feels and how the brain interprets signals from the muscles. This can make it harder to guess the right number of reps left.
In warmer environments, the body works harder to cool down. This extra effort can make muscles feel tired faster, even if they are not close to failure. As a result, someone might think they have fewer reps in reserve than they actually do. The heat can also make people feel more fatigued overall, which can affect their judgment.
On the other hand, cold temperatures can make muscles stiff and less responsive. When muscles are cold, they do not work as efficiently, and this can make it feel like there are fewer reps left in reserve. Cold can also slow down nerve signals, which means the brain might not get accurate feedback from the muscles. This can lead to underestimating how many reps are actually possible.
Wearable devices that track heart rate and other body signals can help give a clearer picture of how the body is responding to temperature changes. These devices use sensors that measure things like heart rate and skin temperature. When the temperature changes, these sensors can show how the body is reacting, which can help people make better guesses about their reps in reserve.
It is important to pay attention to how the body feels in different temperatures and to use tools like wearable devices to get more accurate feedback. This can help people make better decisions about how many reps to do and when to stop, no matter what the temperature is.
Sources
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https://academic.oup.com/milmed/advance-article/doi/10.1093/milmed/usaf528/8307737
https://spaceflightnow.com/2025/11/17/spacex-launches-joint-nasa-european-sea-level-monitor/
https://www.nature.com/articles/s41598-025-22781-x
