This article has been taken from the Runners World website

If you’ve been running well and your muscles feel fine, stretching might seem like a waste of good running time. But scheduling in some stretching could slash your chance of getting injured, help you recover from existing injuries and could even boost your muscles’ performance on the track.

Why?

Stretching helps prevent sports injuries by increasing your range of movement and reducing the tension in your muscles.

Every muscle in the body has an opposing one that works against it – quads and hamstrings, for example. Each of these muscles provides essential resistance to the other, and if one becomes stronger or more flexible the imbalance could result in injury. Hamstring tears, a common running injury, are caused by strong quads pulling against weak, inflexible hamstrings.

Increasing your range of movement means an increase in the distance your limbs can travel before they incur damage – so your muscles work harder for you and your running.

When?

You’ve probably heard about the risks of stretching cold muscles, and might avoid stretching before sessions. But it’s actually best to stretch both before and after sessions, with stretching sessions that achieve different things. 

After warming up with a brisk walk or jog, pop in a short stretching routine before you crack on with your main training session. Taking time to stretch (gently) at this point will help prevent injury. Start by stretching to 50-60 per cent of your range of movement for 10-15 seconds, and increase this slowly as your flexibility increases.

When you’ve finished your session and cooled down, don’t just stop. A few minutes’ stretching will reap huge benefits, preventing tight muscles, reducing the symptoms of Delayed Onset Muscle Soreness (DOMS) and helping your muscles recover by flushing out waste and circulating fresh blood. This means you can get going again quicker, and with less risk of causing strains to tired muscles.

Make sure you put stretching at the heart of your routine, and pencil it in on a regular basis when you’re designing training schedules.

Types of stretching

There are two reasons to stretch – for maintenance of muscles, and to develop muscles – and two chief ways of stretching: static and dynamic.

Static

Static stretches are performed without movement. Simply pick a position, hold the stretch for a period of time and then slowly relax out of it. For example, a static calf stretch is achieved by sitting down and touching your toes with your leg straight out in front of you. Make sure you’re stable and relax into and out of the stretch – wobbling and jerky movements can cause injury.

Passive stretches are very similar, but use a partner or piece of apparatus to stretch the muscles further. For example, stretching the hamstrings by lying down with your leg in the air, and a partner pushing against that leg. Passive stretches achieve a greater range of movement are great for rehab. However, the bigger force and longer stretch increases the risk of injury from stretching this way – so pick your partner with care!

Dynamic

Dynamic stretching uses controlled bouncing or swinging to stretch the muscles. Stretching the hamstrings and hip flexors by standing shoulder width apart and swinging one leg backwards and forwards is a dynamic stretch. Using a stretch to replicate the actions of a sport, or ‘muscle sequencing’, comes in especially handy for faster running and sprinting. If you’re trying out a dynamic stretch, make sure maintain control of the movement, and keep it slow to avoid injury.

How to stretch safely

Before you get stuck in, take a few moments to try a few gentle stretches to assess your flexibility. You don’t want to dive in over-enthusiastically and cause injuries.

Stretch safely with these commandments:
  1.  If a muscle group doesn’t feel 100 per cent, avoid stretching it. If it’s recently strained, only stretch it very gently.
  2. Warm up – increasing the temperature of your muscles makes them more supple and pliable so you’ll get the most out   of your stretches. It also signals your body to supply your muscles with plenty of oxygen and nutrients.
  3. Stretch each muscle’s opposite number to avoid imbalances in strength and flexibility – a recipe for injury.
  4. Stretch for the right purpose at the right time – before exercise to prevent injury; afterwards to aid recovery.
  5. Stretch gently and slowly to relax muscles and avoid strains and tears caused by fast, jerky movements.
  6. Stretch only to the point of tension – you might ‘feel the burn’, but do not put yourself through pain.
  7.  Breathe easy. Lots of people accidentally hold their breath, causing muscles to tense and making stretching harder.       Breathing steadily relaxes your muscles and supplies them with oxygen.