Having hit his mid-50s, former Olympic runner Roger Black thought the fact he sometimes nodded off in front of the TV in the early evening was “just a sign I was becoming an old git”. Similarly, Roger, now 58, blamed ageing for the fact that over the past couple of years he would get so tired driving back from speaking engagements, he would pull into a service station for an energy-boosting cup of coffee “every half an hour or so”.