Sand fit - using the beach to get fit
For sports like beach volleyball (and I'm an ex-volleyball coach), beach soccer or beach rugby, moving and executing a range of movements quickly and effectively is an excellent way of toning the body, particularly where the sand is soft and your feet and core-body muscles have to adjust to the movement of the sand underfoot.
For those from the UK who typically associate beach sports with gentle games of french cricket on damp, hard-packed UK beaches it can be quite a revelation to find that for top performers, playing on sand is more demanding that games like squash or basketball.
For those of us beyond our competitive prime, the beach can still be the perfect place for exercise outside the summer months. it is best to choose soft sand areas rather than the easier work you'll find at the edge of the sea. The softer sand will cushion your movements allowing you to jump, run and if particularly energetic, dive and throw yourself around.
In addition, because the soft sand gives way under your feet, you have to be able to adjust your balance in response. So unlike jogging on tarmac where the effort is mainly in the legs and you can develop a slow and steady trot, things like running on sand require you to use your core-muscles - your stomach and back for instance - in order to keep balance and keep the movement going, thereby giving you a fuller workout. Secondly, because your feet will sink into the sand to get them out and make the next step requires more knee lift than on tarmac.
What this tends to mean is that you will have a shorter and more intense workout which involves the whole body and not just specific muscles just by working out on sand.