A study of fit amateur cyclists aged 55 to 79 found that many were physically and biologically much younger than most people of the same age.
The 81 male and 41 female participants underwent extensive tests of their heart, lung, neuromuscular, metabolic, and hormonal functions.
Their reflexes, muscle and bone strength, and oxygen uptake were also measured, as well as mental ability and general health and well-being.
The results showed that among the cyclists the effects of ageing were far from obvious, with younger and older members of the group having similar levels of muscle strength, lung power and exercise capacity.
Men and women had, respectively to be able to cycle 100km in under 6.5 hours, and 60km in 5.5 hours
Those speeds are commuting / utility speeds.