How tight should a chest strap be?

Snug enough that it does not slide when you raise your arms, but not so tight that it restricts breathing. Most manufacturers recommend placing it just below the chest muscles. Moistening the sensor pads before workouts improves contact.

How long do chest strap batteries last?

Most use CR2025 or CR2032 coin cells lasting 300-500 hours of active use. At 5 hours per week, that is over a year. The Garmin HRM-Pro Plus uses a snap-on module that makes replacement tool-free.

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