Welcome to Midlife Cycling!

Excerpt from an article by John Hughes

Ultra Marathon Cycling Association

Our bodies peak when we are in our 20s and then start to decline. Although the rate of decline may be less in active people, overall we slow down. The changes include:

The amount of oxygen the heart can deliver to the working muscles — VO2 max — declines due to a reduced maximum heart rate and decreased stroke volume, the amount that the heart pumps with each stroke.
As we age we lose muscle mass. Fast twitch fibers (recruited for heavy workouts like climbing) are lost faster than slow twitch fibers, because we rarely use the former in daily activities. We also lose muscle flexibility and range of motion. Fortunately, the remaining muscles’ ability to process oxygen and deliver power is unchanged.
Due to reduced elasticity of the lung’s tissues and increased resistance in the airways, maximal expiratory ventilation declines with age.
Lactic acid, produced by anaerobic riding, is not dissipated as rapidly in older individuals and hard efforts are more difficult to maintain.
Older riders are less tolerant of heat extremes and sweat less in hot, dry conditions.
The older cyclist produces more urine during exercise, meaning reduced blood volume and more time off the bike.
Aging weakens the immune system and older riders may be more susceptible to colds and overtraining.

Although some decline is inevitable, studies comparing active and inactive individuals suggest that much of the slowing with age is a result of individual decisions. About half of the performance decline is due to inactivity and one-quarter is the result of less intensity during training. Thus, the key to maintaining vigor is to ride frequently and intensely. For example, one study of active racers showed that 40 km time trial times declined an average of only 20 seconds per year after age 35. (Friel, J., “Cycling Past 50”, Champaign, IL, 1998, pp. 4-17)