Enjoying a plate of lean protein and vegetables at Street and Co. in Portland, ME, Joe Friel explained that cycling performance (endurance performance, for that matter) begins to decline by about .5% per year beginning at age 35. (Maybe that missing 1.5-2% explains why Lance Armstrong had such a tough time at the Tour de France over the past two years?) The decline in aerobic capacity continues at a fairly predictable and gradual pace until about age 75 at which time, cycling performance "falls off a cliff."
Dr. Murray, a sports medicine specialist at the OA Centers for Orthopaedics, opined that the tricky balance between overload and recovery for a younger athlete becomes even more challenging for a well-aged or mature athlete. That balance, if not managed correctly, could result in the decline in cycling performance as we age. Joe agreed and further speculated that future research might show that the decline is a function of a change in endurance-related enzymes in the body in addition to known declines in growth hormone and testosterone. We all thought it would be great to dig deeper and consider doing a long-term study of endurance athletes over time.
Joe and his son, Dirk, are both involved with Training Peaks software. Over the past 10 years or so, endurance athletes by the thousands have entered data about their workouts in a structured way into Training Peaks, where the data is stored and maintained. Over the fast five years (since 2005 or so), that data has become much more sophisticated with the increasingly common use of power meters and heart rate monitors to measure cycling performance and GPS devices to track running performance. We all thought it would be pretty cool to be able to dig into that data one day and select athletes to study over time.
Joe mentioned that he had been observing one aging athlete for about 10 years. When he started working with him, the guy was 66 years old and one of the strongest guys in the local group (Phoenix, I think). Just this year, at age 76, the guy announced that he was going to stop racing. Joe says his friend is still one of the strongest 10 guys in the group at age 76! Nevertheless, Joe predicts that cycling performance for his friend will quickly decline as he stops racing, likely due to a decrease in aerobic intensity. The correlation between exercise intensity and cycling performance is a theme that continues to develop.
The New York Times recently reported on a Germany study that compared the cells of various age groups and included two sets of athletes, a group of 20-year old runners and a group of 50-year old runners. Both of these active age groupers ran an average of 48 miles per week (the older folks actually ran 50, while the younger group ran 45). When comparing slothful youth to their active, running counterparts, their cell telomeres were virtually the same. (Cell telomere length is an indicator of cell age and is believed to be an indicator of age). But, when they looked at the cell telomeres of 50 year old sedantary folks, telomere length shortened by 60%. They then looked at telomere length of the active, runner 50-year olds. Not only did this group look substantially younger than their sedentary cohort, but their cell telomeres had only shortened by 25% on average, suggesting that regular endurance exercise had kept both the cells and them much younger.
More to come on this fascinating topic of cycling performance and the aging athlete.