I empathise with Dr Lee Wei Ling ("Accepting I can't outrun Father Time"; Nov 15).

It has been said cynically that we start dying once we reach 18.

The body goes into a state of entropy. Muscles weaken and are replaced by fat, bones become osteoporotic and fracture easily, joints develop bony spurs and arthritis, nerves lose their regenerative capacity so responses become tardy, ligaments harden so that litheness and suppleness gradually evanesce, and the heart loses capacity to pump, causing stamina to deteriorate.

While exercise helps to hold back the pernicious effects of senescence, an overdose of it is as pernicious as a lack of it.

Repetitive strain injuries are extremely common.

The very fortunate ones whose joints are seemingly indestructible can pound the streets till they are octogenarians with impunity. But most others have joints that capitulate under a punishing routine of excessive jogging or other forms of aerobics that stress and strain the joints in unnatural ways.

We should recognise the limitations of our bodies and exert within the limits of our frailty.

Exercising for competition is very different from exercising for health. One doesn't need to run marathons nor spend hours in the gym to keep fit.

An avoidance of the bed when one should be up and about, an active lifestyle which includes doing housework and other chores, coupled with some brisk aerobic activity three to four times a week, have served humans well since time immemorial.

Nobody outruns Father Time.

Yik Keng Yeong (Dr)