RACING AND AGEING: WHAT IS THE REAL ASSOCIATION?

1. RACING AND AGEING: WHAT IS THE REAL ASSOCIATION? Michael Turnbull 2nd November 2005

2. OVERVIEW • The participation of adults over 40 in competitive sport has increased dramatically. • Triathlon has a highly competitive age-group scene. • However, ageing will lead to a decline in performance.

3. OVERVIEW • Areas to be addressed: • Does ageing affect performance? • Physiological changes and ageing • How trainable are middle-aged athletes? • Does intensive exercise pose any health risks?

4. SPORTING PERFORMANCE • Swimming • 1500m times decline steadily from the age of 35 onwards. • Cycling • 40km times decrease at about an average of 20secs (0.6%) a year. • Running • A declination rate of about 1% per year from the age of 27-47 can be seen in 10km times.

5. BODY SIZE • Height is lost and weight is gained. • Height loss can start to occur as early as 35. • Weight gain generally begins between 25-45.

6. BODY COMPOSITION • However, training can attenuate these changes

7. RELATIVE FAT MASS (%) BODY COMPOSITION & TRAINING • Regular training in older athletes can maintain body composition to similar levels as sedentary young people.

8. STRENGTH • Strength can decrease by approximately 1.8% per year from 35 years. • Maximal and dynamic strength is reduced. • Active people experience a shift towards slow twitch muscle fibres. • The total number of muscle fibres and fibre cross sectional areas decrease with age.

9. STRENGTH & TRAINING • Strength and resistance training is an important aspect. • Research has shown that ageing does not impair a person’s ability to increase muscle strength or muscle hypertrophy. • Individual muscle fibres also have the ability to grow in size.

10. CARDIOVASCULAR FUNCTION • Endurance performance declines with age. • Max HR decrease less than 1 beat per year • HRmax = [208 – (0.7 x age)] • Max stroke volume and cardiac output decrease.

11. CV FUNCTION & TRAINING • Studies indicate that CV changes are minimized in older athletes who continue to train. • Stroke volume can be maintained in older athletes who have continued to train. • Physical inactivity plays a bigger part than the ageing process.

12. RESPIRATORY FUNCTION • Vital capacity and FEV decrease linearly with age • Residual volume increases • Maximal expiratory ventilation decreases. • These are primarily caused by a loss of elasticity in the lung tissue and the chest wall. • Total lung volume remains unchanged

13. VO2 MAX • Aerobic capacity decreases by approximately 1% per year. • The primary limiter of VO2 max is the decreased oxygen transport to the muscles. • Similar results have been found for highly trained endurance athletes - although the variation is much wider.

14. VO2 MAX

15. VO2 MAX & TRAINING • High intensity training should not be reduced. • High intensity training leads to significantly smaller decreases in VO2 max. • Endurance training improves muscle’s oxidative enzyme activities.

16. EXPOSURE TO HEAT • Older adults are more susceptible to fatal heat injuries. • There is a reduction in thermal tolerance and regulation • Even when people are matched for body size, comp, VO2 max, and acclimatization, these age related differences persist.

17. TRAINING ADAPTATIONS • Endurance exercise training produces similar gains in healthy people, regardless of their age, sex or initial level of fitness • Training cannot halt the process of biological aging, but it can lessen the impact of ageing on performance.

18. CONCLUSION • Ageing affects physical performance • Cardiorespiratory function, strength and body composition are all impaired with age. • It is clear that much of these changes is attributable to inactivity. • Physical activity leads to changes that are similar to that seen in young adults. • Age is not a barrier!