"Training in soft sand may burn between 20 to 60 % more calories than training on compact surfaces." These were the findings of a study led by Paula Zamparo of the University of Verona.
The study showed that the energy cost of walking in soft sand was, on average, 1.8 times greater than on compact terrain.
Zamparo maintains that this is because the recovery of potential – and kinetic energy is much less in comparison to walking on a firm substrate. On the other hand, when running in sand the reduced recovery of elastic energy accounts for roughly 1.2 times more energy required than when running on a compact terrain. Sand training is a simple, low-impact form of resistance training. Walking in sand requires 2.1 to 2.7 times more energy. This increased resistance helps improve quickness and build explosive strength because the muscles experience a greater workload during training exercises.
According to Sean Ryan, physical therapist, and owner at Positive Energy Physical Therapy in Redondo Beach, California, sand running is one of the best ways to help prevent injuries. He adds that not only does sand running strengthen muscles in the core, legs, ankles, and feet, but it can also help to fix your form.
So generally speaking, sand as a training substrate offers more resistance. This added resistance places a higher demand on muscle groups such as glutes, quads, hamstrings, and calves, which leads to a greater workout. And the benefits don’t stop there. With training in soft sand comes uneven surfaces, which in addition, calls for smaller stabilizing muscles and core muscles to engage.
Recovering from injury or looking for an intense workout without the impact? Running in the sand may be the answer. Various studies have shown that, when comparing similar workouts on grass and sand, the latter resulted in significantly fewer inflammation markers measured and perceived DOMS. According to Martyn Binnie, a physiologist at the Western Australian Institute of Sport, with every footstrike there is almost four times less of an impact force when treading on so sand versus firm ground. Training at similar intensities in the sand may thus minimize musculoskeletal load while still reaping the same cardiovascular benefits.
There were no differences in 24-hour post-exercise performance, no indications of muscle damage, and rates of inflammation and hemolysis were similar between each surface.
These results suggest that performing a sport-specific conditioning session on sand as opposed to grass can result in a greater physiological response, without inflicting any additional damage to next day performance.
Athletes can use sand surfaces to improve performance without worrying about recovery or performance issues. Sand training requires less stability and energy returned during exercise, which results in a greater workload for the muscles to achieve the same output.
Training barefoot in soft sand makes runners fast while strengthening everything from hip flexors to tendons and ligaments.
Caution: Running in soft sand also puts extra strain on calves and the Achilles tendon.
***Experts advise to avoid sand workouts for runners with a history of Achilles problems and to stop if calf pain is experienced. ****
Shaun Ryan also warns of an increased risk for micro trauma because sand is such an unstable surface. He advises using sand training sparingly like you would hill repeats or track work. He advises liming sand training to once or twice weekly with sufficient recovery in between by running on firmer surfaces.