In the gym: After the first three weeks of my new regime I met up with Alex Wolf to discuss the programme he had devised for me. Instructors recommend this to everyone so that questions can be asked and any problems resolved.

So far I've been happy with my programme and have followed the small weekly increases without any major difficulty. I'm not ready to run the marathon just yet, but it's very satisfying to initially do six minutes on the treadmill but keep extending it by a minute each week. Even Paula Radcliffe had to start somewhere.

I tell Alex that I'm happy with the bike, treadmill and cross-trainer but would like to go over some of my resistance work again. Despite having some details written down, it's still hard to be sure you've remembered everything and are doing the exercises properly.

Alex is happy to check through them all, as apparently this is where many people go wrong and could be working ineffectively or even dangerously.

Squats' are something I have never mastered. These are very beneficial for leg and bum muscles but, despite varying instructions and advice, I have never been able to perform them without straining my back and staggering about like a cowboy the next day. But, sqats are in my programme at Teddington using a swiss ball (like a large beach ball) between my lower back and a wall, therefore providing support.

This works well but has still been a little uncomfortable. Alex watched what I was doing and apparently I'm leaning forward slightly and not sticking my bum out far enough. Certainly not the most attractive of poses, but now I'm doing them correctly it's not hurting my back and I'm on my way to having a rear to rival Kylie's.

I also took the opportunity to moan to Alex about my problem with the superman' exercise - ie not always finding space to balance star shaped over a swiss ball.

But he wants me to continue this as the arm and leg raising is great for strengthening lower back muscles, so he suggested doing the same exercise but without the swiss ball if the gym gets busy.

I still enjoy the novelty of following my programme and have yet to hit boredom barriers. But I can envisage needing a bit of variety in the future, to keep up the exercise enthusiasm. Thankfully, Teddington not only has a swimming pool but also a range of classes.

I recently heard Janet Street-Porter say that jumping around in a room full of women, and having to look at their sweaty buttocks in leotards, was her idea of hell. I don't feel quite that strongly about aerobics classes but admit I've never been a huge fan. So I took a deep breath and decided to check out what Teddington has to offer.

Aqua Fit: I was a little suspicious about this, imagining some type of scary synchronised swimming, but it's just normal exercises except you're in the water. You don't even need to swim and it's ideal if you're looking for some gentle exercise.

The woman stood next to me in the pool said she'd recently had a hip replacement operation and had been wary of doing exercise. Aqua fit is perfect for her as the water takes the strain off your joints. The class wasn't quite challenging enough for me, but I could feel how the water provides extra resistance for muscle toning.

Super Circuits: And now for something completely different. The instructor places various stations' around the room - mixing cardiovascular tasks like star jumps or stop-start running with strength exercises such as sit-ups or weights.

We work round the stations, moving on when instructed. It may sound like the army, but I found myself really enjoying this class. It's not like aerobics where you have to keep in time and worry about getting your grape vines in a twist. And the different activities kept my mind occupied; I didn't look at the clock once.

This is one for the men too - whereas most classes are female dominated, this one attracts an equal balance.

Legs, Bums and Tums: I now understand where the expression feel the burn' comes from.

Good old LBTs remains a faithful favourite with women of all ages and the class at Teddington is no exception. The instructor varies the amount of cardio work involved but it's always fairly exercise based.

The less jumping around she does, the more you are on the floor exercising, and the more it hurts.

Personally I don't really enjoy this class while I'm there, but it's very satisfying afterwards when you know you've worked hard on the body parts you are least happy with - as they say, no pain, no gain.' Funk Aerobics: This is a class to really get your heart pumping. Its name hints at some requirement for dance skills but, luckily for me, you don't need brilliant co-ordination to take part. It's a fun class for anyone who enjoys being energetic to 80s music and there's a real feel good factor. An invigorating start to your Saturday - providing you can drag yourself there for a 10am start.

Teddington also offers step, spinning, yoga, pilates, Body Pump' and Nifty Fifties'. Classes will definitely provide a varied way of maintaining my enthusiasm for exercise, offering a change from the gym when I feel like it. A change is a good as a rest after all, well, maybe not in this instance.

But after the first half of my six week trial I am feeling much less tired and lethargic than usual. I would have expected all this activity to be tiring, but it seems to have the opposite effect. The rumours appear to be true, exercise really does give you more energy.

So things remain positive and I look forward to meeting up with gym instructor Alex again to assess exactly how my fitness has - fingers crossed - improved over this six week period.