![Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET](https://www.cnet.com/a/img/resize/c7c441cb6aaaaaab2c03f0c0e833b6fdf744cccf/hub/2014/11/20/2b4eef50-b6e6-4a90-a19e-755b53f16f30/polarm400.jpg?auto=webp&fit=cover&height=482&width=856)
Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET
Polar - Extremes are easy. To help strike the right balance between rest, recovery and training—Polar M400 owners can now check out their training load, and recovery status, on Polar Flow. http://updates.polar.com/
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