What it trains
Running mainly trains your heart and lungs, your ability to keep going. In your legs, the calves, quads and glutes do most of the work, while the hamstrings and hip flexors bring each leg forward. Unlike most machines, you land with your full body weight on every stride. Your tendons, joints and bones get worked too, and they usually adapt more slowly than your fitness. Uphill, your glutes and calves take more of the work, and downhill your quads do more braking.
Common mistakes
- Running every session too fast. Keep most runs easy enough to hold a conversation, and save the hard work for one or two sessions a week.
- Adding too much at once. Your fitness improves faster than your legs can adapt. Increase distance or pace, not both in the same week, and take an easier week now and then.
- Running through pain. Tired legs are one thing, a sore knee, calf or shin is another. If it hurts, rather than just feeling hard, stop running and have a doctor or physiotherapist look at it.
Variations and alternatives
- The treadmill when you want to run indoors or hold an exact pace and incline.
- A brisk walk is the right start if it has been a long time since you ran.
- Outdoor cycling trains your fitness without impact, for example the day after a hard run.
- Stair running gives short, tough intervals much like hill running.
How to plan your sessions
If you are new, alternate one to two minutes of running with one to two minutes of walking for 20 to 30 minutes. Start every run with a few minutes' walk or easy jog, as the guide to warming up describes. Two to four runs a week is a good target for most people, and the guide on how often to train explains how running can sit alongside strength training.
Once you run regularly, one hard session a week is usually enough, for example 4 to 6 hard three-minute intervals with two minutes of jogging in between. Build time first and pace second, adding a little at a time in line with progressive overload, so your legs can keep up. Log time and distance, so you notice when the same route starts going faster.