The most common running injuries are to the muscle or tendons. Stronger muscles are less likely to tear, and will also hold the foot in place so that tendons aren’t pulled and stretched beyond their natural limit.( Source)
Unless you’re unlucky enough to have a fall, injuries tend to build up over time, as the pressure you’re putting on your body exacerbates any minor issues. Across an average year, 40-50% of runners will experience some kind of injury (Source), and the figure soars to 90% for marathon runners. (Source)
It tends to be the feet or knees that get injured, but that doesn’t necessarily mean that they’re the source of your problem. Physiotherapists often use simple tests of balance, like getting you to stand on each leg in turn with your eyes closed.
If you’re wobbling all over the place, then you should proceed cautiously when trying to run long distances. I would always urge caution of a patient showed significant muscle imbalances, especially if they haven’t run for a long time. Years of lounging around at university and sitting in an office will have a negative effect on the body’s soft tissues, tending to leave people much stronger on their dominant side. (Source)
Not all imbalances are due to muscle weakness, though: some people are just asymmetrically shaped. This can be caused by injury or a medical condition like scoliosis, but in most cases, people simply have one leg slightly longer than the other. (Source)
If the difference is only a few millimetres, you probably won’t notice that you’re ever-so-slightly lopsided until you take up running and wonder why your hips hurt so badly.
It’s usually recommended that new runners to incorporate strength training into their regime – simple, silly-looking activities like picking up a pencil with your toes (Source) can target the muscles which get a beating when you run. This is important if you’re coming back after an injury, because muscles start to atrophy after just a few days of disuse and you can’t launch straight back at your previous level. (Source)
Strengthening exercises are widely recommended by physiotherapists and trainers, but there hasn’t been much research done on whether they actually prevent injury. All you can do is stick to what feels comfortable and avoid the known risk factors. (Source)
The longer, more often, and further you run, the more likely you are to get injured (Source), and if you’ve been injured once you’re likely to get hurt again. (Source) Of course, you have to take that with a pinch of salt: if you’re a runner who never goes for long, often, or far, then you might as well take up Pilates instead.
There are some things proven to reduce the risk of injuries, such as easing into training gradually, keeping your distances below 40 miles a week (Source), and wearing well-fitted shoes. Standard warm-up and cool-down exercises don’t make a difference to your risk of injury, and neither does stretching – but they don’t make things worse, either, so do what feels right for you. (Source)
The muscles you use for running are also the muscles you strengthen by running. If you’re a new runner, strength training exercises may help, but it’s far more important to ease into the activity gently: for example, start by hiking, or alternate short bursts of jogging with periods of fast walking. Of course, some people won’t have any option but to pause, panting and red-faced, every fifty yards. For new runners who are already fairly fit, though, it’s important to take it easy even if you feel like you could go further. The more years you’ve been running, the less likely you are to get symptoms– so if you do get injured, don’t give up.