By the end of a long run, it’s often your calves that tell the story. They tighten first, ache longest and quietly decide how smooth or clumsy those last miles feel. What’s easy to overlook is how much they’re doing beyond propelling you forward. Scientists refer to the calf muscles as your “second heart” because every contraction helps push blood back toward your chest, keeping your circulation steady even when your heart rate climbs.
Scientists are beginning to emphasize the importance of calf health, even for non-runners; however, for runners, it’s especially critical. Here’s what makes your “second heart” so vital, and how to take care of it so it can take care of you.
4 calf-strength moves all runners should master
How it works
Each time your calves contract, they press against the deep veins in your lower legs and move blood upward through a series of one-way valves. This muscle action prevents blood from pooling in your feet and lower legs, especially during long bouts of standing or running. If those muscles are tight or under-trained, circulation slows and swelling can develop. Over time, limited motion also alters your stride and adds pressure to surrounding joints.
Why it matters for runners
Along with keeping blood moving, strong calf muscles steady your ankles and help your legs absorb the shock of each step. When that system starts to falter, fatigue builds sooner, and the soreness that follows a run tends to hang around longer.
Three simple ways to strengthen your “second heart”
Heel raises: Lift and lower with control, focusing on the full movement from heel to toe. Perform two or three sets several times a week.
Mobility work: Include ankle circles or knee-to-wall stretches after a run to keep joints flexible and maintain full range of motion.
Active cooldowns: After finishing a run, walk for a few minutes instead of stopping immediately. Gentle movement keeps blood flowing and helps prevent lightheadedness or pooling in the lower legs.
