A mixture of cycling and running - about half-an-hour every day.
What got you started?
I was never sporty at school. Ten years ago I was getting wobbly and decided I should try to lose some weight.
Why cycling and running?
For years it was just cycling, because I love it. Sadly, it was becoming increasingly difficult because of the traffic, and I was knocked off my bike a couple of times. So, last June I took up running, with the occasional bike ride for variety.
How do you make time?
I like to exercise in the mornings, so I go into school early dressed in my running kit. I run round the playing fields, shower in the sports hall and get changed for work.
Have you felt the benefits?
Yes. I'm less flabby and less grumpy. If I miss a few days I notice a difference immediately. And I don't get ill as often as I used to.
The aches and pains. At my age I have to spend as much time warming up and warming down as I do exercising. Even then the occasional muscle pops, which is frustrating. There's nothing you can do but wait for it to mend.
How active are your colleagues at school?
Most are very active. In fact, I was shamed into action really by my staff being such a fit bunch. We have a running club, where teachers and pupils run together.
Start earlier than I did: if you leave it late you're making life hard for yourself. And the "no pain, no gain" saying is very true. I could easily have quit early on, but I'm glad I didn't.
Bernard Trafford, 47, is head of Wolverhampton grammar school. For tips and ideas on personal fitness go to: www.tes.co.ukgetactive