Heart rate Monitor: Best ones are by Polar. You can get fancy ones, with GPS built in, or just a simple one that tells you your heart rate.

心率监视器：最好是带指北针的，或者更奢侈一点，带有GPS导航功能，或者简单到仅仅能显示你的心率。

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A smart, intuitive training computer for runners and cross-training athletes, the Polar RS300X G1 wrist heart rate monitor helps you to train at the right intensity with personal training zones.

一个聪明，跑步者和交叉培训运动员的直观培训计算机，极地RS 300 X G1的手腕心率监测有助于你在正确的强度训练与个人训练区。

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