We all know exercise is good for the mind as well as the body, thanks to the endorphin release. But did you know that just assuming a different posture can help too? Take Harvard researcher Amy Cuddy's advice and spend two minutes in a "power pose" — stretch out your arms to the sides, raise your chin, and open your chest. This open body language will actually change your brain chemistry — yoga mat optional (and less than £10 if you choose to buy one!).