Here is my beach bootcamp secret. Have each member bring a pillow case. They can fill it an appropriate amount of sand weight for their level. Tie a knot and let the lunges, presses and pain begin!
It you have access, kettlebells and medballs go a long way on the beach!
And that doesnt wokr there are endless bodyweight exercises when performed with proper form will kick their asses! Good Luck Coach Briody