The Aging Athlete

By Laura Lundquist, FCAMPT, MScPT, BSc, Cert. Sport PT, Dip. Manipulative Therapy

The aging athlete faces a number of unique challenges as he/she attempts to maintain a physically active lifestyle.  These challenges are primarily a consequence of the age-related physical and physiological changes that begin on average during the fourth decade of life.  This section will outline these major physical and physiological changes and their repercussions on activity frequency, intensity, duration and type for aging athletes.  It will also discuss the impact of these changes on rehabilitation protocols following injury.

Normal Age-Related Physical Changes:

Joints

A common complaint identified by the older athlete is   a loss of flexibility which can affect performance as well as increase the potential for both acute and chronic injuries.  Changes in flexibility can be attributed to the properties of ligaments.  The viscosity of aging ligaments decreases causing structural weakening with decreased compliance (decreased elastic behaviour).  Tissue compliance is lost as a result of increased cross-linking between the collagen fibres of the ligament and decreased synovial fluid in the joint capsule.  The functional result is decreased joint flexibility.  This generally doesn’t cause clinical dysfunction but if there is associated bone pathology and abnormal stresses, the ligamentous changes can further contribute to joint instability and permanent deformity.

Muscles

Peak strength is gained in the third decade of life and plateaus until approximately age 50.  Between age 50 and 65 there is a decline in strength that progressively continues after age 65.  The loss in strength is due to declining physical activity as well as a muscle fibre type change from Type II to Type I (fast twitch to slow twitch).  A decline in protein synthesis relative to degradation and decrease in connective tissue viscosity also contribute to a generalized loss of strength with aging.

However, research has now shown that the aging athlete can still engage in a weight-training program and make significant gains in strength.^₆ 

Balance

An increased incidence in falls in the elderly population is well-documented and is likely due to age-related changes in strength, flexibility, sensation and balance strategy (tendency to hip vs. ankle balance response).  However, balance can be positively impacted by improvements in strength, flexibility and proprioception.¹

Aerobic Fitness

Aerobic fitness is variable between athletes and is due to a number of musculoskeletal as well as cardiorespiratory factors.  The key determinant of aerobic fitness is VO2max; which is the volume of oxygen that the body can consume during maximal physical exertion.  VO2max generally begins a progressive decline at approximately age 30 by 10% per decade.  However, endurance training can positively affect this energy system despite the natural aging process. 

There is evidence that aging athletes require more time for recovery between maximal workouts; they typically score higher on perceived levels of fatigue and muscle soreness than younger athletes of comparable ability.  Therefore, if a younger athlete normally has 24 hours between near-maximal workouts, the aging athlete may need 48-72 hours for optimal recovery.⁴

Repercussions for Rehabilitation:

Although aging athletes may suffer from the same acute injuries their younger counterparts experience, they also have a higher predisposition to chronic injuries and other conditions such as tendinopathy, osteoarthritis and osteoporosis. 

The reduction in collagen matrix and reduced overall flexibility of aging joints can cause increased strain on the musculotendinous unit.  This increased strain (especially when participating sports causing unidirectional strain on a single structure) can result in tendinopathy (ie: the Achilles tendon in running).   Underlying differences in available range of motion and collagenous resiliency may require smaller ranges of stretching and increased rest between sets and between bouts of exercise.

Osteoarthritis typically affects the large weight-bearing joints of the body.  It commonly affects the knees, hips and lumbar spine in the aging athletic population involved in impact activity.  Sustaining repeated high impact forces through a joint affected by osteoarthritis often results in increased symptoms. In consultation with sport medicine health practitioners (eg. Sport Medicine Physicians, Orthopedic Surgeons, Sport Physiotherapists), aging athletes with mild to moderate osteoarthritis may need to incorporate non- or low-impact activity for cross training purposes to limit the impact to the affected joints.  However, athletes may also be counseled to participate in shorter events (ie: 10Km runs vs. Marathons) or consider lower impact activities. 

Peak bone density is attained mid-way through the fourth decade of life.   Following peak attainment, there is a gradual reduction of bone mass density in aging male and female, athletic and sedentary populations that can result in osteoporosis.  This loss is due in part to hormonal changes (more in females than males; particularly post-menopausal) but also to an age-related alteration in the bone resorption/formation relationship whereby the rate of resorption surpasses that of formation.  Bone density can be positively impacted by changes in diet, vitamin intake and exercise.  The physiotherapist treating an aging athlete may consider a referral to a Registered Dietitian to address if his/her food intake is proportionate to his/her exercise regimen.  Exercise should include low to medium impact aerobic activity and resistance training (depending on the degree of boney degradation).  An underlying diagnosis of osteoporosis in the aging athlete must also be considered when designing rehabilitative exercises (eg. plyometric training may be inappropriate if the bone density is insufficient to sustain the force without eventual fatigue fracture).

In conclusion, maintaining an active lifestyle through the later years of life is continuing to gain popularity in the older adult population.  The sport physiotherapist must consider the issues special to this demographic to optimize rehabilitative treatment and return to sport.

Resources for more information:

Healthy Canada’s Info for Healthy Active Living for Seniors
http://www.hc-sc.gc.ca/hl-vs/physactiv/index-eng.php

Physical Activity Guide for Older Adults (Public Health)
http://www.phac-aspc.gc.ca/pau-uap/paguide/older/index.html

Article from ADVANCE (PT magazine)
http://physical-therapy.advanceweb.com/Features/Top-Story/Aging-Athletes.aspx

CNN article re: Aging Elite Athletes
http://www.cnn.com/2009/HEALTH/07/16/athletes.comeback.endurance/index.html

About.com links to multiple articles
http://sportsmedicine.about.com/od/olderathletes/Older_Athletes.htm

References

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2.    BMJ 1997;315:1065-1069Chen, A., Mears, S., and Hawkins, R.  Orthopaedic Care of the Aging Athlete.  J Am Acad Orthop Surg, Vol 13, No 6, October 2005, 407-416.
3.    Donato, A.J., K. Tench, D.H. Glueck, D.R. Seals, I. Eskurza, H. Tanaka. Declines in Physiological Functional Capacity with Age: A Longitudinal Study in Peak Swimming Performance. Journal of Applied Physiology, 2003, 94(2):764-769.
4.    Fell, J., L. Haseler, P. Gaffney, P. Reaburn, G. Harrison. Performance During Consecutive Days of Laboratory Time-Trials in Young and Veteran Cyclsists. Journal of Sports Medicine and Physical Fitness, 2006, 46(3): 395-402.
5.    Fell, J., P. Reaburn, G.J. Harrison. Altered Perception and Report of Fatigue and Recovery in Veteran Athletes. Journal of Sports Medicine and Physical Fitness, 2008, 48(2): 272-277.
6.    Hurley B.F., Roth S.M. Strength Training in the Elderly: Effects on Risk Factors for Age-Related Diseases.  Sports Medicine, Volume 30, Number 4, October 2000 , pp. 249-268(20).
7.    Thompson, L.V. Skeletal Muscle Adaptations With Age, Inactivity, and Therapeutic Exercise. Journal of Orthopedics, Sports, and Physical Therapy, 2002, 32(2): 44-57.
8.    Zachezewski, J., Magee, D., Quillen, W.  Athletic Injuries and Rehabilitation.  Saunders.  1996.