Cardio machine readouts

[anonymous-user]

How seriously should I take the stats displayed on gym cardio machines?

I spent 45 minutes on a stepper with a medium step depth, 120 steps per minute, burned 1000 calories (4 Mars bars!), averaged 180-200 watts and 8.0 METs, and climbed 300 storeys.

I’ve seen an increase in the stats since I started training so they're useful in that respect, but I don’t really trust them as absolute values. I already ignore the heart rate because it once told me that my towel had a BPM of 135.

[KamSandhu44]

Not very seriously. Most are completely wrong.

The machine doesn't know your height, weight and other stats.

I wear a Polar H7 heart rate monitor while I do my cardio, the output from that is completely different to what the machine tells me.

[digger_R]

Any half decent polar/suunto HRM will be streets ahead of the generic stuff on gym equipment, though it's useful enough for relative measures eg. one training session compared to another

[anonymous-user]

I actually have chest-strap heart rate monitor somewhere (bought for when I was doing a skydive, but that's another story....). Is there a way to derive energy used based on heart rate?

Cyclists seem to like their power meters (i.e. the number of watts they're putting out). Would the wattage shown by cardio machines not be fairly accurate, given that they're measuring a mechanical output of power rather than some biological function?

[944fan]

Wattage will be more accurate than calories, but wattage is only any use if you know what you are looking for and what to do with it. If you want to use power to train you have to an FTP test to find your power zones.

Anything measuring calorie burn other than lab equipment will be wrong by a fairly large margin.

But not to worry, the calorie counts on food packaging can be +/- 25% of actual.