Lactate Threshold ZonesSports Science

Convert Maximum Heart Rate (MHR) or Functional Threshold HR (LTHR) into targeted athletic training zones.

Parameters & Inputs
Threshold Heart Rate (LTHR)168 bpm
Physiological InsightLactate Threshold represents the highest exercise intensity you can sustain without lactic acid accumulating faster than your blood can clear it.
Interactive Analytics & Output
Reference Pulse Baseline (LTHR)
168bpm
Zone 1: Active Recovery
< 143 bpm< 85%

Light active recovery; flush lactic acid; very low exertion.

Zone 2: Aerobic / Endurance
143 - 150 bpm85% - 89%

Building fundamental aerobic capacity; primary fat-burning zone; comfortable conversational pace.

Zone 3: Tempo / Aerobic Capacity
151 - 158 bpm90% - 94%

Improving aerobic power; carbohydrate burning; sustained tempo effort requiring high concentration.

Zone 4: Sub-Threshold / Sweet Spot
160 - 166 bpm95% - 99%

Optimizing anaerobic threshold; rapid glycogen usage; heavy breathing.

Zone 5a: Super-Threshold / LTHR
168 - 171 bpm100% - 102%

Sustaining peak aerobic speed at lactate threshold boundary; intense localized muscular burning.

Zone 5b: Aerobic Capacity (VO2 Max)
173 - 178 bpm103% - 106%

VO2 Max intervals; anaerobic cellular metabolism; extremely hard intervals.

Scientific Sports ConditioningUse these metrics to systematically optimize athletic performance. Heart rate targets help structure endurance capacity, while power ratios and mechanical variables allow fine-tuning efficiency.

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