Running laps is the least useful conditioning a player can do

A match is several hundred short accelerations and hard stops, and steady state running trains almost none of what that demands.

The image of pre season is a squad jogging round a park in the cold. It looks like work. It is work. It is largely the wrong work.

Break a point down honestly. Four shots, maybe eight, occasionally twenty. Each shot is a step or two of acceleration, a plant, a rotation, and a stop. Total distance covered in a long rally might be thirty metres, in bursts of three or four. Then twenty seconds of standing still. What that pattern demands is the ability to produce force quickly, absorb force eccentrically without the tissue giving up, and repeat that a few hundred times over three hours while recovering in short windows.

Distance running builds the recovery half of that and works against the first half. Long slow mileage nudges the neuromuscular system toward efficiency and endurance at the expense of how quickly force can be produced. Spend a winter doing it and you will feel fitter, in the sense of being less out of breath, and be slower over the first two steps, which is the only distance tennis ever measures.

The half that gets neglected almost everywhere is deceleration. Stopping is more demanding on tissue than starting. The muscle is lengthening under load, the forces at the knee and hip are higher than in the acceleration phase, and this is where the injuries actually occur. Yet the standard court coverage drill has players sprinting to a cone and jogging back, which trains starting over and over and lets them off the hook on the part that hurts.

Better drills accept ugliness. Sprint to a mark and stop dead, hold the position for a full second so the eccentric load is genuinely absorbed rather than bounced out of. Lateral shuffles that finish with a hard plant and a change of direction on a call, so the athlete cannot pre plan the stop. Repeated low jumping with a stiff ankle, which is what a split step actually is. None of that photographs well.

My one concession to the joggers is the aerobic base. You need it, particularly for five set formats and for recovery between points, and forty minutes of easy work a couple of times a week gets you most of it.

The rest of the time, train the stop. The sprint takes care of itself.