When we swim in winter our muscles get cold and their ability to contract and expand is impaired, especially so in the arms, and shoulders area, where we have a high surface to mass ratio. The chances are, if you have swam through winter before, you may have felt a strange muscle tightness across your shoulders. This is always my signal to get out as soon as possible. When muscles get really cold, they just can’t function correctly, so this months move is a really nice dynamic stretch to get those shoulders feeling wonderful again, but only once you are fully warm again after your winter swim!