Training harder not longer

Our national newspaper had an article last week extolling the virtues of working out harder, not longer, as we age. Interestingly, this nugget of wisdom has been revealed to be true even for younger athletes (although technically we're all aging, even if we're 10 years old). Physiology research has shown for some time that intensity work is the "right stuff" as far as exercise goes: it's the hard work that makes real changes to key fitness indicators like resting heart rate, resting metabolic rate, production of mitochondria and capillaries.

That's why, in class, we focus on interval speed work. For those of you who love the speed work, it's usually because the endorphin high kicks in quickly. For those of you who don't like it, you seem resigned to the fact that it does make a difference.

Many of us are training for marathons and half marathons, so training for longer is an essential part of our training tool kit. Still, it's good to know that if we stuck to interval training once a week and set our sights on 5k events, we'd stay in great shape and still have fun.

Also, if your long training walks can't happen for some reason, it's reassuring to know that fitness levels can be sustained by intensity work - exercising where your exertion feels like 8 or 9 on a scale of 10.

So go blast out a few intervals and let us know how it feels.