A year of fitness: Gym tips

Following on from my previous post on getting fitter and healthier, here are a few things I’ve learnt about gym based exercise. Might be of interest to those starting out.

Clothing

I’d recommend spending the money and getting proper gym clothing. You can just use an old T-shirt but cotton is horrible for cardio work, you’ll just get sweaty without working as hard as you could[1]. Proper wicking material is more comfortable and you’ll get more done. Be careful with running tops, they can be cut quite slim, because runners are stick insects. They’re also quite short, if you lift something over your head the shirt will ride up and everyone will see your belly. Important note: Nobody wants to see your belly.

Similar applies to shorts as well. After initially being a sceptic, I now prefer shorts with a built-in liner which functions as underwear. Sports underwear exists as an alternative, but either way, cotton isn’t much fun. Sweaty seams on briefs are just going to encourage skin problems.

Nothing stinks like stale gym kit. Rinse, either hand or machine, on the day of the gym and then air, ideally in the sun, until wash day. When washing, normal detergent struggles as it’s too viscous. Performance cleaner for Gore-Tex and similar will work, but pure soap is good too and much cheaper.

Heart rate monitor

About six months in I bought a heart rate monitor (HRM). I was worried this was just part of my ‘bombard a hobby with gadgets’ tendency, but I’ve found it useful. I chose a Suunto M2 which seems to be as good as Suunto devices get before they become annoying and start nagging you to do certain things on certain days. It’s a chest-belt based monitor, as I read that the optical wrist only ones weren’t as reliable. The belt isn’t a problem, you quickly forget about it.

One of my initial reasons for buying a HRM was a worry I was pushing myself too hard for my age. There are various ways of calculating maximum heart rate but the consensus seems to be that I shouldn’t be going above the low 180s, which I interpreted as a safety limit.

As it turns out, this number (like so many things in biology) is an average and people vary a lot. I suspect I’m actually a ‘high beater’ in that my heart runs quicker than most for a relative level of exertion. An example heart rate zones calculation says my zone 5 (90% level, essentially sprinting) starts near 170bpm, when in fact I can hold this effort for over ten minutes as part of a cardio block with no ill effects. This means that, for me, treating 180bpm as a working maximum is conservative, but that’s OK. Targeting 170–180bpm as my hard-work rate leaves me nicely tired at the end of a gym visit, but not seeing stars.

HRM showing 182bpm

Calorie counting

Another initial reason for the HRM was to get a calorie count for the whole session. The HRM will do that, but as time has passed I’ve stopped caring for a few reasons.

Firstly, there’s a question about accuracy of the calculation. Some of the cardio machines produce their own calorie count and these can be 50–100% greater than the HRM measurement for the same period. I’d expect the HRM to be more accurate as it knows more about me, in particular my heart rate, but the fact such variations exist doesn’t inspire confidence. I also doubt it takes account of the afterburn effect.

Secondly, the values don’t seem to vary very much against how hard I work. If I do a two hour gym session, it will be around 1000kcal ±5%, so really it functions as a crude clock. This doesn’t mean the numbers are wrong, just that calories burned are a poor proxy for effort. For a given calorie burn I could have pushed myself to a new personal best or just cruised round.

Lastly, the temptation is to use the calorie measure to offset food intake, but that’s a whole other barrel of frogs in terms of understanding how your body metabolises different kinds of food at different points in time.

The result is a number I don’t trust, and isn’t very useful anyway. As a measure of effort I now prefer the HRM’s time-spent-in-each-zone measure. Even if I don’t agree with the zone boundaries, this correlates better with how hard I feel like I’ve worked. A good session would include 40 mins above zone 3, a poor session is below 20 minutes.

Music

As well as alleviating boredom, the right music does help, and the better songs can inspire a good 10bpm difference on a cardio run. I’ve been using a Sansa Clip, which is cheap, and small enough to clip onto clothing.

Everyone has different experiences with gym headphones. In general I don’t like earbuds for any use, but the choice of on-ear gym/sweatproof options is limited. There is the Philips SHQ5200 but as these are designed for runners they deliberately don’t provide much ambient noise insulation, so the user doesn’t get hit by a bus. For gym use you want the isolation to block out the default MTV accompaniment.

I’m now using Sennheiser CX685s, but note the default tips are horrible. With Comply T400 tips they block out more ambient noise, sound better, and fall out less.

  1. Don’t fall into the trap of thinking more sweat means more achievement. Sweat is just a cooling function. [Back]