If untrained guys eat a high-fat diet for 7 weeks, their muscles use less stored sugar during medium-intensity exercise compared to eating a high-carb diet — it’s like saving their fuel — but their legs still take up the same amount of glucose from the blood.

Even when eating almost no carbs after a race, athletes who’ve been on a high-fat, low-carb diet for months can still rebuild their muscle sugar stores just as well as those eating lots of carbs.

After biking really hard and then eating a lot of carbs for a few days, your muscles store way more energy than they do after running hard and eating the same way.

After a short, super-hard workout, your muscles refill their energy stores way faster than after a long, slow one—even if you eat the same amount of carbs.

After a tough leg workout, drinking a sugary sports drink instead of water helps your muscles refill their energy stores faster, so you recover better after six hours.

After a really hard workout, eating a lot of carbs helps your muscles rebuild a special type of stored energy (macroglycogen) much better than eating fewer carbs.