Do calf raises help achilles tendonitis or make it worse?

Not recommended: Stretch rather than loading will help tendonitis. So will using a roll over soled shoe, changing your gait or running distances, and rest. Physical therapy can guide your progress and apply anti-inflammatory techniques. Good luck.

Worse: You want to rehab the tendon under control. Stretch gently and use ice when the area is tender. A podiatrist and physical therapist can help to prevent a rupture from occurring.

Depends: Depends on how long you've been battling it. For acute tendinitis, it's best to let the tendon rest initially but then progress through active rehab which would include calf raises. If its chronic, or tendonosis, eccentric calf exercises work best. Eccentric means resistance while lengthening the muscle and tendon, such as standing on a step on your toes then slowly lowering your heels.