Beach sprints:
There are a couple of benefits I found for running on sand versus concrete, and they are:

1. Much less of an impact on your knees, ankles and hips.
2. Strengthens your weak points- forces you to use the smaller muscles in your lower body.
3. They make you burn calories extra fast through a combination of the hot sun, and unstable ground beneath you.
   Next time you’re at the beach, see how different it is!