Indoor-only players get injured more often than those with beach time. Why hard hardwood stresses your knee more than soft sand — backed by a real study.
"Is indoor handball really more dangerous than beach handball — or is that just a feeling?" — straight talk: it's not a feeling, it's documented research. A study by Degenhardt et al. (2025) compared athletes who play beach handball alongside indoor with indoor-only players — over three years and 641 athletes. Result: indoor-only players logged 295.8 injuries per 1,000 athlete-years, while those who also played beach handball in the off-season logged only 225.3 — a reduction of roughly a quarter, purely from sand time in the off-season.
The mechanism behind this is biomechanically well explained: sand training measurably lowers the knee abduction moment on landing (the sideways-caving force on the knee) and anterior tibial translation relative to the femur — exactly the loading patterns that frequently lead to ACL injuries in handball. Translated: sand cushions your landing like a mattress, hardwood barely gives at all.
Where the injuries land most often is also clearly documented: 66.1% of all injuries affect the lower extremity (knee, ankle, thigh), 26.3% the upper extremity (shoulder, elbow, fingers). For you as an indoor player, that means your legs carry nearly two-thirds of the total injury risk.
295.8 versus 225.3 injuries per 1,000 athlete-years is no reason to panic, but a clear signal: the hard indoor floor challenges your body differently than a soft surface. Knowing that lets you train more deliberately against exactly this risk.
Sand training measurably reduces knee abduction moment and tibial translation on landing — both risk factors for the ACL. Hardwood lacks this natural cushioning effect, so your own musculature has to take over that job.
The strongest practical lever from the study: summer breaks with beach handball instead of complete training silence. You train proprioception, jumping power and change of direction on a forgiving surface — without the load of hardwood.
Because 66.1% of all injuries happen there, landing training, lateral stability and ankle work belong at the very top of your prevention plan — even ahead of pure strength work for arms and shoulders.
The remaining 26.3% mostly involve the shoulder, elbow and fingers — usually from throw volume and body contact at the circle. A prehab program for the throwing shoulder still makes sense, even though leg risk is higher.
The higher injury load in indoor handball isn't a reason to avoid the sport — it's a reason to counter it deliberately. A structured knee-stability and landing program, well established in sports medicine, lowers exactly the risk factors that a hard floor amplifies.
Warm up thoroughly before intense jumping and stopping movements, and deliberately schedule recovery time during heavy load spikes — overtraining raises the risk further.
If your club has a summer beach handball squad: join in, even if you see yourself as a "pure indoor player." The evidence suggests that exactly this sand time noticeably lowers your injury risk in the following indoor season — one of the few prevention measures that's also fun.
Yes, concrete numbers show it: 295.8 versus 225.3 injuries per 1,000 athlete-years among players who also played beach handball. The hard indoor floor is the key difference.
Because it reduces knee abduction moment and tibial translation on landing — both central risk factors for ACL injuries. Hardwood doesn't offer this natural cushioning.
The lower extremity, with 66.1% of all injuries — knee, ankle and thigh. The upper extremity makes up the remaining 26.3%.
The evidence clearly supports it: athletes with beach handball time in the off-season had roughly a quarter lower injury risk in the following indoor season.
Indoor Handball: The Jump Shot Against a Closed Defense