For integrating heart rate monitoring into your training, this watch enables you to track your avareage heart rate and pre-set target heart rate zones with data for time spent within that zone and alarms. It also offers up to four linked interval timers, each with its own target zone, and a recovery timer that measures your heart rate after a timed recovery during or after your workout. Other features include:

• 5 interval timer workouts with warm-up and cool-down
• 100-hour chronograph with lap and split, either in large digits
• 100-lap memory with average heart rate per laps
• 100-hour, 3-mode countdown timer
• 5 alarms with daily/weekday/weekend options
• 2-year battery life

The Indiglo night-light uniformly lights the surface of the watch dial using patented blue electroluminescent lighting technology. It uses less battery power than most other watch illumination systems, enabling your watch battery to last longer. The Night Mode feature allows you to illuminate the Indiglo night-light for 3 seconds with any button press, regardless of the mode or function. The watch is water resistant to 50 meters (165 feet)--suitable for swimming but not for diving. All Timex heart rate monitor sensors have batteries that can be replaced by consumers without requiring them to be returned to the manufacturer.