Ever wondered why your shoulders ache after a long run? This is because your upper back and shoulders are too tensed up. The back scratch warmup exercise can help relax your back muscles before your run.

• While standing, reach one arm up and bend the elbow to pat your back.
• Reach your fingers down your upper back as far as you are able to.
• At the same time, put your other hand behind your lower back and reach your fingers up your back as far as you can.
• Try and touch your fingertips.
• Repeat 5-10 times per side.

It's all right if you can't touch your fingers; make sure you don't overextend yourself. This exercise is also great for releasing the tension in your shoulders after extended periods of sitting down!