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Pain and the treadmill - Ed's journal
Pain and the treadmill
Well, I've been paying a bit more attention to workloads down the gym recently. I don't know if you'll be aware, but I spoke to a doctor about ... well, my health in general, and one of the upshots of the discussion was that I'd actually been working too hard at the gym.
Sounds a bit daft, I know.
But the way it works is this - there's a basic formula of conservation of energy - energy out vs. energy in - which determines whether you gain or lose weight. And at an absolute level, it doesn't really matter if you use up 500 calories in 2 minutes, or 200 minutes.

What it comes down to though, is how your body is utilising it's energy, and where it's drawing power from - for 'short term/high demand' energy usage, it'll use sugar in your bloodstream - it's the most easily accessible energy source, and when you really need to run away from that lion that's chasing you, that's what you need to use.
But the thing is, you don't actually hold much energy there, and so you'll quickly become tired as the free sugars in your blood get used up, and your body has to switch over to other energy sources. Whilst you can keep going, it'll be at a lower work output, and you'll be tired out until you can rest. (Which makes it way harder)

But if you think about it, you can spend several hours walking without feeling tired. And that's because your body is keeping that 'blood sugar' available in case a lion pops up, and is instead using less easy to access energy sources - your body fat. Which may well be where I've been going wrong - I get bored easily, and so have been working on the assumption that 20 minutes (20m being the time I can get away with if I go out in my lunch break, but the principle applies to the longer sessions that I used to do) of 'working as hard as I can' was the way to go. And it's not, because what that does is burns the blood sugars out of my bloodstream, and leaves me tired for a few hours, without actually using up that much energy in the process.

So the trick is to figure out the work load at which you're utilising which energy sources - thanks to my medical a few weeks ago, I've got a fairly good idea of which points that happens at. I've now got myself a heart rate monitor, and ... well, basically you figure out your max heart rate, which as a rule of thumb is 220 - your age. You then exercise at a threshold maintaining your heart rate between certain limits - about 70-80% max heart rate (so in my case 130-150). Some gym's have exercise machines that'll even monitor the heartrate and adjust workload accordingly. (That's surprisingly unpleasant actually - just as you're starting to slow down, it cranks up the difficulty to keep your heart rate up)

Anyway, we'll see how that goes. Certainly I've made it to the gym most work days over the last couple of weeks. Today I tried a cross trainer for the first time, and really did notice that it uses different muscle groups to the rower - some muscles that aren't so used to that kind of workout, and are protesting a little. But so it goes, it's a good idea to mix up what you're doing anyway, as that way you work different muscles on different days, and so don't end up straining them. (After a workout, it takes a while to 'recover' completely, so you don't actually do yourself any favours by doing the same exercise two days in a row - it'll work, it just means you're retreading ground that you don't need to, at the expense of other muscle groups).

The good news is the number on the scales is down, although having a scale that fluctuates by 2-3kg makes it a little hard to tell at times.
7 comments or Leave a comment
From: dj_rws Date: May 13th, 2009 08:20 pm (UTC) (Link)
Well done on finding a good balance. I've not been doing as much exercise as I would have liked since starting my current job so decided on a 4 mile run around the countryside on Sunday. But it did get me thinking about the whole weight loss thing and it is why those marathon runners hit "the wall" when after constantly running for 3-4 hours or so there just simply isn't any energy left and it becomes really hard to do anything. I guess that's the reason they're all sticks and need to eat like sumos the night before running a marathon!
mister_jack From: mister_jack Date: May 13th, 2009 09:15 pm (UTC) (Link)
If you want to track your weight, make an excel spreadsheet and keep a daily record of it with a trendline showing where it is headed.
sobrique From: sobrique Date: May 13th, 2009 09:55 pm (UTC) (Link)
I have one of those, but it doesn't help that I can weigh myself 3 times e.g. this morning, and get a 2-3kg spread on the readings.
I guess a correlation fit of all the readings I do get might do the trick.
mister_jack From: mister_jack Date: May 14th, 2009 08:11 am (UTC) (Link)
Do it at a set time, like before breakfast, and it should be a bit more consistent and - as you say - the line of best fit should dampen out most of the random error.
velvet_nothing From: velvet_nothing Date: May 14th, 2009 09:07 pm (UTC) (Link)
I'm doing this at the moment! I'm recording calorie intake for the day and my 8pm weight every day. If I lose weight over the course of the month, which I do seem to be doing, I might even make a spangly graph! Er, if I can figure out how...

I find that when I drop a pound or two, it goes lower one day, up and down again for the next day or two, then settles, which is when I feel I have 'really' lost it. Then after a few days it dips and fluctuates again.
paulw From: paulw Date: May 15th, 2009 08:52 am (UTC) (Link)


When Yak was down here we used to go and play squash.

I've been thinking of doing it again so it you want to have a go let me know and we'll arrange a game.
sobrique From: sobrique Date: May 15th, 2009 10:35 am (UTC) (Link)

Re: Squash

I recall giving Yak a game once. It wasn't exactly my finest hour, as I ended up ... well demonstrating just how horrendously unfit I was. I mean really, I am pretty sure he was taking pity on me as I looked about to have a heart attack, but it really wasn't muhc of a game of squash. I don't generally mind the notion of learning to play, but my level is ... well below one at which I'd give anyone else a meaningful challenge to play against.
7 comments or Leave a comment