What paddling does for you:
muscles, mind and mood

In sports where only the legs do the work, the picture is different: kayaking is one of the rare disciplines that mobilises the entire upper body in a single fluid motion. Each paddle stroke chains a pull from the back muscles (latissimus dorsi), a contraction of the shoulders and biceps and, above all, a trunk rotation driven by the abdominals and obliques. Because this activation is continuous and repeated, the activity burns calories so effectively: muscle never stays idle, and the cardiovascular system carries a constant, moderate load throughout the outing.

Sports scientists use the following to estimate energy expenditure objectively: MET (Metabolic Equivalent of Task). One MET corresponds to the energy you burn sitting still at rest. A leisurely paddle on calm water sits at around 4 METs, a steady active tour climbs to roughly 6.5 METs, and intense or upstream paddling can reach 10 METs — a value comparable to running or vigorous swimming. The higher the MET, the more calories you burn per hour for the same body weight.

Your real expenditure depends on two factors: your body weight and the intensity of the session. A heavier paddler moves more mass with every stroke and therefore burns more. For a 70 kg person, expect roughly 280 kcal per hour on a relaxed outing and up to 700 kcal per hour in sustained sporting effort. Because the resistance of the water is constant and the gesture symmetrical, the energy is spent smoothly, without the jarring impacts of running — which makes the calories burned both substantial and joint-friendly. Use the interactive calculator below to obtain a figure tailored to your own weight and chosen intensity.

The reputation of kayaking as a back-breaker comes almost entirely from one mistake: paddling while slouched in the seat. When the pelvis tilts backwards — what specialists call retroversion — the natural inward curve of the lower back (the lumbar lordosis) flattens out. The intervertebral discs, which act as shock absorbers between the vertebrae, are then squeezed unevenly at the front, and the pressure they undergo rises to its maximum. Repeated over a long descent, this posture is exactly what can lead to disc strain or, in the worst cases, a herniated disc.

The solution is the opposite movement, tilting the pelvis forward, into anteversion. "Sit tall" and let the buttocks press toward the back of the seat, and you restore the natural lumbar arch. In this position the load is shared properly along the whole spine, and the deep paravertebral muscles lining the backbone are gently engaged to keep you upright. Far from damaging the back, a well-positioned paddler actually strengthens these stabilising muscles stroke after stroke, building a postural endurance that also protects the spine in everyday life.

Good technique is about more than sitting up straight. The real power of a stroke comes not from the arms but from a rotation of the trunk, initiated around the navel. By turning the torso to plant the blade far ahead, you recruit the large back muscles and the obliques instead of overloading the small muscles of the arms and shoulders. The legs play their part too: by bracing the feet against the footrests and pushing alternately, you transfer energy from the lower body into each stroke and lock the pelvis firmly into its protective forward tilt. Mastering these three elements — a stable paddling frame, trunk rotation and leg drive — is what turns a potentially harmful repetitive gesture into a genuinely back-friendly one.

Few activities can be started at eight years old and still enjoyed at eighty, and kayaking is one of them: the same gentle, low-impact motion can be turned up or down for every stage of life. From one age group to the next, it is not the gesture that changes but the priorities: a child learns coordination and confidence, an adult manages stress and keeps muscle, and a senior preserves mobility without straining the joints.

For children and juniors (8–14), kayaking is a superb tool for psychomotor coordination and balance, but it comes with one non-negotiable prerequisite: being able to swim at least 25 metres. Young paddlers also lose body heat far faster than adults, so warm clothing and short, playful sessions of around one hour are the rule. For adults (15–60), the aim shifts to stress relief and muscular upkeep, and an ideal rhythm is two to three sessions a week; the key technical reminder is never to skip the stretching that keeps the back supple. For seniors (60 and over), the great strength of kayaking is that it is a "supported" sport, carried by the water and therefore gentle on arthritic knees and hips; the only genuinely delicate moments here are getting in and out of the boat, when balance matters most, so a very stable kayak with a wide cockpit is strongly recommended. The tabs below give detailed advice for each group.

Kayaking is a remarkably safe activity, but like any outdoor water sport it carries a few specific risks that are easy to prevent once you know them. They fall into three categories — one biological, one thermal and one musculoskeletal — and none of them should deter a sensible paddler.

The first is leptospirosis, sometimes called "rat's disease", a bacterial infection carried in rodents' urine that can contaminate fresh water. The risk is low but real, and the precautions are simple: never swallow river water, cover any open cut before launching, and shower thoroughly once you leave the water. The second is hypothermia. On a river, wind and humidity together cool the body far faster than the air temperature alone suggests, and cold sets in quickly after a capsize. A neoprene wetsuit or thermal layers, worn even when the sun is out, are the best insurance. The third is tendonitis, which typically hits the rotator cuff of the shoulder or the wrists when the paddling load is too high or the technique poor. A proper warm-up, good hydration and a clean, rotation-based stroke that spreads the effort across the whole body instead of yanking with the arms keep these overuse injuries at bay. The cards below sum up each risk and its prevention at a glance.