Heart rate training
Although there are many subjective clues as to how your body is doing during exercise (perceived exertion, breathing rate, physical sensations), none of them are as reliable as measuring heart rate. It is objective and affected by both internal and external factors—meaning that you will have a dependable measure of your physical state.
Measuring heart rate with your OH1
To measure heart rate accurately you need to wear your OH1 snugly around your forearm or upper arm or with the swimming goggle strap holder on you temple. The sensor must be in constant touch with your skin, but the armband should not be too tight to prevent blood flow. The sensor in the swimming goggle strap holder should be attached as far as you can on your temple without getting your hair between the sensor and your skin. For most accurate heart rate measurement, we advise you to wear your OH1 for a few minutes prior to starting the heart rate measurement.
Do not press the sensor button while under water to maintain water resistance.
If you have tattoos avoid placing the sensor right on them it as it may prevent accurate readings.
Also it's a good idea to warm up the skin if your hands and skin get cold easily. Get the blood going before starting your session!
For detailed instructions on wearing OH1, see Wearing your OH1