Caffeine may hide tiredness without restoring muscle function, so feeling better does not always mean you have recovered. The Frontiers article discusses caffeine’s effects on exercise, effort, and recovery. It draws on earlier studies involving trained athletes and people exercising for recreation. The key point for our Post-Exercise Fatigue (Excessive) community is simple: feeling less tired and being recovered are different things. In endurance exercise, caffeine may help athletes perform better at similar effort or leg pain levels. But changes in how exercise feels were not consistent across everyone studied. The supplied excerpt gives no effect sizes, caffeine doses, or group sizes. It also does not show that caffeine treats prolonged tiredness after exercise. The article warns that hidden fatigue could lead to doing too much. Someone might push harder while their muscles still need recovery. That could affect movement quality or leave too little time for rest. Caffeine-related sleep disruption may also affect repair and other recovery processes. The concern goes beyond the number of hours spent asleep. For members tracking their own patterns, this separates workout performance from later recovery. A useful log could pair caffeine amount and timing with workout details. It could also include a simple tiredness rating that evening and over the following days. Sleep Duration adds another piece of context, though it cannot capture every part of recovery. Comparing similar workouts may make community notes more useful. A strong session after caffeine is worth recording, alongside how you felt afterward. Those patterns cannot prove cause and effect, but they can reveal questions worth exploring together. What have you noticed about caffeine, workout performance, and your energy over the following days?