You might think that running very, very slowly to become much, much faster is right up there with eating more cake to lose weight. For the marathon runner Sue Gardener, though, slowing down has been the secret of her running success.

Before she started her slow-to-fast journey, though, Gardener needed to invest in some electronic gadgetry. "I bought a heart-rate monitor after my second marathon,"says the 44-year old from Hayling Island in Hampshire. "I found a thread on the www.runnersworld.co.uk forum about something called base training' and thought I'd give it a go."

Building an endurance base by slowly adding mileage to steady runs is a tried and tested technique, but base training using a heart-rate monitor (HRM) is an idea conceived by the American coach Phil Maffetone. Maffetone has coached world class triathletes including the legendary Ironman champion Mark Allen. He developed a formula - known as "180 minus" - to determine the highest heart rate you should reach during the first three months of a training year. Gardener was intrigued enough by this idea, and especially the positive feedback the technique was receiving from other runners, to give it a try.

"My target base-training heart rate seemed to be around 125bpm," she says. "So I started running to this heart rate every day. The pace was painfully slow at first, around two minutes slower per mile than my usual pace. Gradually though my pace improved and I became comfortable running at this low heart rate, but at a faster speed than I'd been running at before."

For beginners, Maffetone's method helps provide an excellent introduction to running. For experienced runners, used to speedwork and tempo runs, heart-rate base training can be very frustrating. You'll want to run faster, as you may find that your base rate pace feels barely quicker than walking. But, if Gardener is anything to go by, sticking it out for a few months before adding harder sessions is well worth trying. She completed her 2004 marathon, before she'd trained with an HRM, in 4:05. One year later she'd improved to 3:47, now boasts a best of 3:31 and is aiming to run under 3:15 at the Abingdon Marathon in Oxfordshire this October.

"I've graduated from base training and now know all the heart rates I need to train and race at," says Gardener. "For instance I know that if I run a marathon at 145bpm, I won't be slowing down at the end or that 156 will result in a decent 10K."

Julie-Anne Ryan is another runner who discovered that her running improved after she purchased a heart-rate monitor and slowed down. "I thought that it would be the perfect way to lose weight," she says, "but I found that I simply couldn't run for more than three or four minutes at a time." Ryan found her inability to keep going so frustrating that she frequently gave up, only to start running again - with the same disappointing results - a few weeks later. Then a friend suggested that she try using a heart-rate monitor during her runs. "The first time I wore it I ran three miles without stopping," she says. Five years later, the 46-year-old from Buckinghamshire is 19kg lighter and still running. "I can honestly say that buying a heart-rate monitor stopped me from giving up completely."

Ryan and Gardener are just two of thousands of runners who have found that using a heart-rate monitor is one of the most effective ways of achieving impressive results. They're also proof that this technology isn't just for fast runners or athletes with degrees in sports science.

"Regardless of your standard, it is good to know what impact any workout is having on your body," explains Joe Dunbar, an exercise physiologist and coach. "Unlike using the subjective marker of how you feel today, your heart rate is an objective measurement of what is going on inside your body."

Ryan's subjective view was that she felt dreadful and adding some objectivity was a massive breakthrough. "I was making the classic beginner's mistake of running far too fast," she explains. "Of course, I didn't realise this, but I bought the monitor, read up on how to use it and when I started training to heart rate, it all fell into place."

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If you fancy trying heart-rate base training then here's the formula developed by Phil Maffetone:

Subtract your age from 180 (180 - age).
Modify this number by selecting one of the following categories:

    If you have or are recovering from a major illness (heart disease, any operation, any hospital stay) or on any regular medication, subtract 10.
  • If you have not exercised before, you have exercised but have been injured or are regressing in your running, or you often suffer from colds or flu or have allergies, subtract 5.
  • If you have been exercising for up to two years with no real problems and have not had colds or flu more than once or twice a year, subtract nothing.
  • If you have been exercising for more than two years without any problems, making progress in competition without injury, add 5.
For example, if you are 30 years old and fit into the second category: 180 - 30 = 150, and 150 - 5 = 145. This is your maximum aerobic heart rate. Maffetone believes you should train at or below this level for at least three months before adding speedwork, threshold runs and races to your repertoire - making it an excellent plan for beginners.

According to Dunbar, Ryan's running improved instantly because she was experiencing the most basic benefit of using an HRM - awareness. "Your body will let you train harder than is physiologically beneficial," he explains. "This means that many people do most of their runs too hard and fall into a trap of running most sessions at the same pace regardless of duration." Working out at a variety of different intensities is fundamental if you want to improve as a runner and an HRM is one of the best tools around for achieving this.

One runner who has realised this is Ross Preston. "Three years ago, my training just didn't seem be helping my running progress," says the 33-year-old from Devon, a Major in the Royal Marines and 3:20 marathon runner. "I'm a man of habit and that extended to my running. I'd head out and run the same route, at the same pace every day, so my race times just didn't improve. I should have known better - I studied exercise science at university." Exasperated at his static race times, he did what many runners do - let alone qualified sports scientists - and bought an HRM. "I found that even if I ran the same route, I could use the monitor to do it at different intensities and within just a couple of months my race times started to improve."

Published: 23 August 2006 full article, including more detailed advice on calculating your training zones and some sample exercise sessions. You can save 30% and get instant access to premium content right here

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