h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I was extremely athletic in my 20s, at my peak 26-28, doing basic exercise routines that included extended push up, pop up from extended position and clap my hands, pop up into regular push up position, 4 kinds of push ups, 2 one handed push ups on each hand, kip (from regular push up position, up position, flip over into situp position, do four kinds of situps, reverse kip, repeat, 25 sets, & other exercises like walking on my hands, hand springs, running at least a mile every day.

Until I was in my middle 30s, my weight was 125 Lbs at 5' 10" then it went up to 150.

In my middle forties, weight went up to 180 Lbs and has been steadily, if slowly, increasing ever since.

Blood pressure was 80/60 until my middle forties, then increased to 120/80. Nowadays it varies erratically with a max like 180 over 140 and lows like 110/70 if I forget to take my blood pressure medication.

MJy son wants to lose weight - and he wants me to support him. Yesterday, he convinced me to go jogging with him. I hadn't jogged for 30 years.

We'll make a food plan, then go shopping this weekend.

The BMI uses the square of your height because using the cube of your height, which you might think would give the right results, doesn't.

The volume of an object is proportional to the cube of its height, but taller people are not the same shape as smaller people. It was found experimentally that using the square rather than the cube gave a better figure.

I believe the BMI is right for me, as I know I am overweight, and I know what weight I was when I felt just right. These correspond to BMIs of 27 and 23.5, which are exactly what the BMI people say they should be.

The main reason BMI is so widely used is that it is a simple calculation. We like simplicity. However, that doesn't make it valid. That it works for people with a "standard" body, doesn't make it valid.

A stopped clock is nice and simple and is valid for certain times.

I don't mind people using BMI to get a general idea of their condition, but I am bothered when insurers make financial decisions for their customers and doctors make medical decisions for their patients based on it.

Again, I point to my case of being classed as overweight at 7% body fat. I was underweight. My body doesn't match the BMI. It's based on 19th century pseudoscience.

Of course, I don't need the BMI to tell me I'm a fat now. . Hell, I'm nearly the shape of that smiley.

Adding good wishes to all the losers!

I lose about 20 lbs a year ago, though some of that has since crept back on. There's a truism that results are 80% nutrition, and only 20% exercise. For me, it was portion control that was key.

(Also increasing proteins and reducing carbs, but that doesn't suit everyone)

That said, exercise is very important, and like a lot of you guys, I've set myself a challenge - I'm running a leg of the relay in the Belfast Marathon on 7 May.

BMI is a good rough indicator, but not the one and only measure.

7 May - that's only week away, Bea!

On height to weight ratios, anomaly that came up repeatedly during my Army years was troops who went in for weight lifting frequently weighing in at over their nominal 'ideal' body weight, well defined abdominal and pectoral muscles, the major muscles on their arms and legs standing out prominently, pressing 3 times their own weight or more on the bench press...

Whatever else, clearly not obese.

There was a supplementary regulation on that involving having them taped for comparison of their height, waistline and other measures.

I don't find that much of a problem to be honest. If I want to tell if someone has a high BMI because of muscle or because of fat, it takes about 30 seconds to take a look and work out the difference.

The problem in the military had to do with the fact that the people doing the evaluations didn't usually have the actual troops at hand for comparison, embarrassing having a muscle building jock written up for obesity when really he was not, hence the supplementary regulation.

Yup, a week away. I have been training since the start of this month, though - running every other day, trying to go a bit faster/ further each time. And I did manage to run a 10k race last Sunday, albeit not very fast.

The ancient Greeks, training for the Olympics, were also trained to affect enjoyment, no matter how painful the ordeal.

Especially the ones from Sardos, presumably

A few weeks into my training programme, the exercises are getting easier. I was given a range of weights, and I've been doing them with the lower end of the range. I'll start upping the weights slightly at my next gym session. My calculations say that at my present rate of weight loss, I'll reach my target in February 2013. I'll try and help that along by changing my diet, too.

Belfast Marathon today!

Bit damp out there, but that's better than blazing sunshine, for running.

Aiming to do my 5.4 miles in under an hour - it's the 4th leg, running alongside Belfast Lough, fairly flat, boring, few crowds.

Fingers crossed! My flatmate's running the first leg and said he'd go cheer everyone else on, so he might be there.

Did it in 54 mins - in the freezing cold, wind and rain, so awful conditions! Worst bit was waiting at the relay handover point, anxiously looking out for the previous leg runners (who'd been doing the most gruelling leg, 7 miles up the Antrim Road)

Light exercise day for me today, since I was constantly on the go the last two days, time to get caught up on my meds and do light work around the house.

I'm continuing my twice-a-week to the gym regime. So far I've only lost 1 kilo, but I'm getting fitter. The weights that were hard to lift four weeks ago are easy now.

Good man -- it's the long haul that counts as well you know.

If I find myself craving junk food, I look at http://thisiswhyyourefat.tumblr.com for ten minutes and feel slightly sick instead