This Suunto women’s heart rate monitor is the exact one I use during every workout. I’ve tried several monitors and most of the straps irritated my skin, but this one fits so that it conforms to my body. There are a ton of features that come with this watch (calorie counting, speed, distance, cadence), but I use it mainly to detect how hard my heart is working.
I can’t recommend a heart rate monitor enough. My trainer insisted that I get one or she wouldn’t work with me, and now I know how hard I’m really working at any given time. Knowing my heart rate during a workout has improved my endurance tenfold. DO IT.
(I found this monitor on my own, they are not paying me to say any of this JUST SO YOU KNOW.)