There’s a rite of passage when you start a new exercise routine or sport: Following your workout, parts of your body may wobble like jelly.
While this experience can happen even with pros, Andrew Jagim, an exercise physiologist at the University of Wisconsin, said that “jelly legs” are especially common with beginners who are not used to working out. “Even doing body-weight squats for five minutes could be enough to make their legs start shaking and quivering,” he said.
Even though this is a natural physiological reaction, it’s still something you’ll want to watch. Unsteady muscles after you use your maximum effort are part of your body’s cry for some rest. From an athletic trainer’s perspective, the signal means: “Hey, it’s time to sit down. Don’t go hurt yourself,” said Patrick Maloney, the lead athletic trainer at Tulane Institute of Sports Medicine in New Orleans.
When this physical shakiness occurs, it means your nerves are short-circuiting and are having trouble communicating with your muscles, Jagim said, because of the rapid onset of fatigue your training is causing. So your body “can’t initiate muscle contraction and relaxing like it normally does,” Jagim explained.
It’s “a temporary state of fatigue, and it’s largely due to the disruption to just how our nervous system and muscles can communicate with one another,” Jagim said.
