Body weight and shape are a consequence of lifestyle, and any
change to them must involve a change in lifestyle.
Exercise is an important component of the lifestyle balance that determines
body weight, since energy taken in from food that is not expended as
exercise is stored as fat.
Exercise is also important for reducing blood pressure and for boosting
"good" HDL cholesterol: both of these changes improve cardiovascular
The recommended level of exercise for best health is either
- Five episodes per week of one hour each at 50% of aerobic capacity
such as brisk walking: at this level you will be breathing steadily
and can chat to a companion, but would have to pause for breath between
phrases, and cannot whistle.
- Three episodes per week of half an hour each at 70% of aerobic capacity
such as jogging: at this level you will work up a sweat and will be
puffing; you would have to pause for breath between words.
The form in which exercise is taken is important because it must be:
- Safe -- cycling in traffic may not be safe
- Enjoyable, or at least tolerable
- Appropriate -- for the obese, jogging is inappropriate
because of the strain it puts on joints and ligaments
- Sustainable -- this is for the long haul, not a flash in the pan
Strategies to consider are:
- Where you can, build the exercise into your daily life --
walk to work or to the shops, use stairs instead of lifts, walk or
jog with a friend
- Choose something that suits you -- if you suffer joint
pain from jogging, consider swimming, aquarobics, using
an exercycle or rowing machine, joining a gym
- Minimise your opportunities to avoid it -- choose a form
of exercise that is independent of weather and winter darkness
If you are keen to find out how you are going in a particular activity,
you can determine the level of exercise you are doing by the effect it
has on your pulse rate. Measure your resting pulse rate: it is commonly
about 70/min. Calculate your maximum predicted heart rate as 220 minus (age
in years): for a 50-year-old, it is 170/min.
Exercise at 50% of aerobic
capacity will take the pulse rate 50% of the way from resting to maximum
-- to 120/min for a 50-year-old with a resting pulse rate of 70/min.
Exercise at 70% of aerobic capacity will take it to 140/min for that person.
You can determine your level of exercise by pausing to count your pulse
rate, and doing the maths.