A word from James...

When I first met Natasha late last year, and she told me about her weight-loss plan, I was immediately interested. Here was someone who didn't want a quick fix and wasn't interested in following the latest fad diet. Instead this was someone who wanted to do it the only way I'd recommend. Slowly but surely.

When we actually started our sessions early this year, she didn't try and con me about her abilities. She was very honest and told me straight that she was hard pushed to run for a bus without collapsing or, at best, being very out of breath. Everyone has to start somewhere and Natasha's first and hardest step had already been taken: deciding to do something about the shape she was in.

The initial tests I asked her to do (steps and squats) proved hard work. In fact, half-way through the step test, Natasha had had enough. However, she persisted and managed to complete the three-minute routine.

Over the past few weeks, I've got her to increase her workload bit by bit, moving through basic exercises (lunges, high knees, split squats), upping the intensity in terms of frequency, time, speed and numbers of repetitions – and I'm pleased to say that, thus far, I haven't needed a resuscitation kit.

In terms of increasing Natasha's aerobic fitness, we first started with walking, then fast walking, then added short bursts of jogging. Once she'd become a dab hand at that, the ratio of jogging to walking increased. Walks became shorter, jogs longer and faster, with less rest before the next activity (bench steps, for example, that she now takes in her stride).

The important thing to remember when you're getting fit is progression. Often clients ask me: 'Shouldn't I be getting better at this by now?' If I'm doing my job as a trainer properly, adjusting each session, the answer is no. There are many tools that trainers use to gauge a client's progress and the fact that Natasha asked me this question the other day was a clear indication that not only was she getting fitter and stronger, she'd not noticed me turning up the heat on our sessions. (Well, not unless I really go for it – then she knows all about it!)

My aim (and it's a highly achievable one) is that by the end of March Natasha will be able to run a comfortable lap of the park where we train, just over half a mile.

At this rate, given the traffic levels on our streets, she'll be beating the bus home any day now!