Running the same routes over and over soon gets dull. And it's also bad news for your body, particularly if you stick to roads and pavements. The forces associated with running on hard surfaces can be more than twice as great as softer ground, so it's no surprise that the journal Medicine and Science in Sports and Exercise reports that harder running surfaces are more often associated with injuries. But not all off-road surfaces have the same benefits.
"Different surfaces influence how much energy is lost during foot contact," explains Dr Sharon Dixon, a senior lecturer in biomechanics at the University of Exeter. "More energy is lost on less 'stiff' surfaces. A very soft surface like sand will dissipate more energy than Tarmac and requires more effort."
No single surface can meet all your performance and injury prevention goals - Dixon believes there is an optimum range of surfaces that place an acceptable level of stress on the joints. So, varying what's underfoot will help you boost your fitness - even if most of your races are on asphalt.
An expanse of golden sand between sparkling sea and sweeping dunes is enough to inspire anyone to fling off their shoes and break into a canter - but beach running can be tough. The energy required is significantly greater than running on grass, says the Journal of Science and Medicine in Sport.
A high energy demand, coupled with a low-impact surface makes the beach a challenging terrain, and involves subtle differences in technique and muscle recruitment. "Running on sand results in a different style as you try to push off the ground," says Dixon. Research from the University of Western Australia found that it increased cadence, shortened stride length and resulted in longer stance phase (total foot/ground contact time) than a firmer surface. The extent of hip and knee flexion on foot contact were greater on sand, and hamstring activation was higher.
If you're accustomed to running mainly on road, Dr Nicholas Romanov, Pose Method founder, advises keeping your initial beach runs short, wearing shoes and avoiding deep, soft sand. However, working up to barefoot beach running and drills
can build strength, he says.
Beach running has its downsides, though. Running on cambered beaches throws the body out of alignment, while soft sand places extra stress on the Achilles tendon and calf muscles compared with firm, even surfaces, according to Medicine and Science in Sports and Exercise.
To play it safe, stick to the water's edge, where the sand is wet and more hard-packed than higher up the beach. Or supercharge your run by taking on the powdery stuff. "Visualise yourself floating above the sand, instead of sinking into it," says Mahon. This, he adds, can only be achieved if you learn to lift your foot off
the ground, rather than pushing it off.
This interval workout mixes running hard on soft sand with slower bouts on the firmer wet sand closer to the water. Aim for 5-10 one-minute efforts on dry sand with one minute jogging where it's firmer underfoot. Continue to zig-zag along the beach.
Sand dune hills
Find a sloping sand dune and after a warm-up, run hard up to the top (or for up to one minute), maintaining a short stride and fast cadence. Jog back down and catch your breath. Aim for 5-12 ascents, depending on the gradient and length of the dune.
Exercises for running on sand
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