Nowadays players maintain great level of fitness and it is not unusual to find 38-39 year olds playing international cricket. Along with Mohammad Hafeez, another player who maintains a good fitness standard is Shoaib Malik. For the batsmen and spinners, it is relatively easy. But that is not the case for the pace bowlers. Wear and tear from heavy workload means that most of them retire by the time they reach 35-36. A few who surprises me with their determination are James Anderson of England and Peter Siddle of Australia (although the latter no longer play international cricket).