How Should a Runner Kick in Freestyle?
Short answer: smaller than you think, from the hip, with loose ankles. Your legs carried you through marathons. In the pool, their new job is mostly to stay out of the way, politely.
The unscheduled race
Watch a runner's first lengths of crawl and you'll often see two sports happening at once. Up front, a swimmer is trying to swim. At the back, a pair of legs is running the 100 metres. Knees bending, feet churning, water flying. The pool looks like a jacuzzi with a person in it.
It's the most natural thing in the world. Your legs are your engine on land. So when you want to go forward, you ask them for more.
In the water, that's an expensive misunderstanding.
The kick is not your engine
Most new swimmers believe a powerful kick drives you forward. In endurance freestyle, the kick has a different main job. It's the co-driver in a rally: it calls the corners, it doesn't grab the steering wheel.
Think of a marathoner's arms. They don't pull the runner forward. They balance the rotation of the hips and keep the rhythm. Take them away and the runner still moves, but wobbles and tires sooner. In the pool, your kick does much the same:
- Timing: it syncs with your arms and rotation and helps organise the whole stroke.
- Hip height: it gives just enough lift to help keep your hips up.
- Balance: it counters the rotation of your body so the stroke doesn't wobble.
The kick still adds some propulsion, especially as speed rises. But for a runner swimming steadily, propulsion comes mainly from the hips and the arms, and big legs cost a lot of oxygen.
What a hard kick actually costs you
Your thighs are among the biggest muscles in your body. Ask them to thrash for 25 metres and your heart rate climbs faster than on your local hill repeats.
Worse, a runner's kick usually comes from the knee. A bent knee pushes the shin forward against the water like a brake. So you work harder and go slower. It's like flooring the accelerator with the handbrake on.
The 10K runner who kicked like a sprinter
Mark, a 10K runner, arrived kicking hard and fast from the knee. He still finished each length with his legs low and his heart rate higher than at the top of his hill repeats.
We filmed him before changing anything. The video showed three things at once: a lifted head, a bent knee on every kick, and a rushed breath. The fix didn't start with the legs at all. It started with the head. Then came a smaller kick from the hip, and a comparison of two rhythms over the same short distance.
He kept the one that gave him the calmest line. The lesson: the right kick isn't always the smallest one. It's the one your body line can use.
2-beat, 4-beat, 6-beat in one minute
| Pattern | Kicks per full stroke cycle | Effort | Best for |
|---|---|---|---|
| 2-beat | 2 (one per arm stroke) | Low | Long, steady swims and open water |
| 4-beat | 4 | Moderate | Steady pace, or when the 2-beat feels wobbly |
| 6-beat | 6 (three per arm stroke) | High | Short, fast efforts |
For many distance runners, a gentle 2-beat is a sensible first experiment. It's a starting point, not a rule. If your hips fishtail or your rhythm falls apart, a soft 4-beat might suit you better. Your body type may hint at what to test first, but the water decides.
What a good kick feels like
A good endurance kick is hard to notice. The legs stay near the surface without you holding them there. The ankles feel loose, like wet socks hanging on a line. The movement starts at the hip, and the knee barely bends.
You should be able to forget your legs for a whole length. If your thighs burn, your heart rate shoots up, or you feel the kick more than the stroke, it's too big.
Try this at your next pool session
Swim two easy lengths:
- Length 1: your normal kick. Notice your breathing at the wall.
- Rest until you're fully recovered.
- Length 2: the same arms, but make the kick half the size, from the hip, ankles floppy.
Which length left you calmer at the wall? Most runners are surprised how little their legs need to do.
Where this goes next
The hard part isn't kicking less. It's timing the kick with your arms and rotation so it helps instead of interferes. From Runner to Efficient Swimmer gives the runner's kick its own chapter: how to find your pattern, how to time it, and how to stop your feet starting their own race when another swimmer jumps into your lane.
Mark's story shows something important: his kick was never really the problem. His head was. That's how swimming works. The kick depends on your balance, your balance depends on your head, and your head depends on your breathing. Fix one part on its own, and another part breaks. That's why tips about the kick alone rarely last. What lasts is learning the stroke as a whole, in the right order: balance first, then breathing, then the arms and the timing of a small, relaxed kick, each stage practised until it runs without conscious thought. A proven process like this reprograms the runner's instinct to drive with the legs and replaces it with a stroke that saves your legs for the run. That's the order the book follows, five stages, each with its own readiness gate. If your thighs burn after a few lengths, you don't need a better kick. You need the whole stroke, built step by step.
Take it easy, God bless you.