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

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.

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?

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 can be seen in 10km times.

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

BODY COMPOSITION However, training can attenuate these changes

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

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.

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.

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.

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.

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

VO 2 MAX Aerobic capacity decreases by approximately 1% per year. The primary limiter of VO 2 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.

CHANGES IN VO 2 MAX AMONGST NORMAL ACTIVE MEN AgeVO 2 max % change from 25 years VO 2 MAX

VO 2 MAX & TRAINING High intensity training should not be reduced. High intensity training leads to significantly smaller decreases in VO 2 max. Endurance training improves muscle’s oxidative enzyme activities.

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.

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.

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!