RACING AND AGEING: WHAT IS THE REAL

ASSOCIATION?

Michael Turnbull

2nd 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 27-47 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 25-45.

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.

0

5

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15

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25

30

35

40

YoungSedentary

OlderSedentary

YoungTrained

OlderTrained

MenWomen

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LAT

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(%)

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

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.

CHANGES IN VO2 MAX AMONGST NORMAL ACTIVE MEN

Age VO2max % change from 25 years

25 47.7 -

35 43.1 9.6

45 39.5 17.2

52 38.4 19.5

63 34.5 27.7

75 25.5 46.5

VO2 MAX

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.

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!