PRIMARY HEART-RATE SENSOR
Polar H10
Chest-strap sensor used for reliable heart-rate tracking during weighted jump rope, where wrist-based optical sensors can be disrupted by arm movement.
DISPLAY AND AUDIO INTERFACE
Apple Watch
Receives the Polar H10 signal and provides wrist display, interval alerts, and audio guidance so the participant does not need to watch a stopwatch.
Protocol Engine
Intervals Pro
Runs the session structure, target heart-rate zones, rope weights, work intervals, and recovery targets.
Why Heart-Rate-Based Rest Intervals Matter
Heart-rate-based work and rest intervals allow beats-per-minute ranges to be programmed and announced by the Apple Watch throughout the workout. Work intervals are time-based, with heart-rate thresholds guiding intensity. Rest intervals are typically based on heart rate alone, with the Apple Watch announcing when the programmed recovery threshold has been reached.
A higher recovery threshold allows the next work interval to begin at a higher heart rate. For example, individuals training at vigorous intensity or in Zones 5 or 6 can use higher recovery thresholds to resume each work interval sooner and at a higher heart rate.
Post-Session AI Analysis
After each session, workout data can be exported and reviewed to evaluate training intensity, time in programmed heart-rate ranges, heart-rate recovery between sets, and progression across sessions.
Recent examples are documented on the My Workouts page.
Apple Watch heart-rate interval screen during Jim’s weighted jump rope training.
Apple Watch vs. Polar H10
During weighted jump rope, wrist movement can interfere with optical heart-rate readings. For that reason, JumpIron uses the Polar H10 chest strap as the primary heart-rate sensor when precision matters.
The Apple Watch remains valuable as the display, alert, and audio-guidance interface.
Timer Selection
Heart-rate guidance is introduced only after an appropriate ramp-up period. Beginners and participants returning after an extended break or injury recovery first progress through this ramp-up before heart-rate-guided workouts begin or resume. Once introduced, Intervals Pro timers are customized for each individual, including target heart-rate ranges, work-interval durations, recovery thresholds, and rope weights.