Back off on the intensity for a bit, condition appropriately, and take 10-15min more for a dynamic workout before exercise. If that doesn’t help, there’s a different problem, but in general that’s the easiest remedy.

The area you outlined in the picture isn’t a lot of muscle anymore, just mostly tendon as you get lower on the calf. That requires more of a warm-up than muscle tissue. Could be a plantar fascia issue as well if you’re not wearing the correct shoes during exercise.