Ventilatory Threshold 1 Vt1 Calculator
Our sports physiology calculator computes ventilatory threshold vt1 instantly. Get accurate stats with historical comparisons and benchmarks.
Reviewed by Sher, Sports Science & Nutrition Specialist
Formula
VT1 VO2 = VO2max x 0.55 (range: 0.45-0.65)
VT1 typically occurs at 45-65% of VO2max and 60-75% of heart rate reserve. It is identified by a systematic increase in VE/VO2 (ventilatory equivalent for oxygen) while VE/VCO2 remains stable. VT1 marks the boundary between moderate and heavy exercise intensity domains.
Worked Examples
Example 1: Estimating VT1 Heart Rate and Training Pace
Problem:A 70 kg runner with max HR 190 bpm, resting HR 60 bpm, VO2max 50 ml/kg/min, and max ventilation 120 L/min wants to find their VT1 zone.
Solution:HR Reserve = 190 - 60 = 130 bpm\nVT1 HR Low (60% HRR) = 60 + (130 x 0.60) = 138 bpm\nVT1 HR Mid (68% HRR) = 60 + (130 x 0.68) = 148 bpm\nVT1 HR High (75% HRR) = 60 + (130 x 0.75) = 158 bpm\nVT1 VO2 = 50 x 0.55 = 27.5 ml/kg/min\nSpeed at VT1: 27.5 = 3.5 + 0.2 x speed -> speed = 120 m/min = 7.20 km/h\nPace = 3600/7.20 = 500 sec/km = 8:20/km
Result:VT1 HR: 138-158 bpm | VT1 Pace: ~8:20/km at 7.20 km/h
Example 2: Determining Training Volume Distribution
Problem:An athlete trains 10 hours per week and wants to follow polarized training based on VT1 at 148 bpm and VT2 at 170 bpm. How should time be distributed?
Solution:Polarized Model: 80/5/15 distribution\nBelow VT1 (< 148 bpm): 10 x 0.80 = 8.0 hours/week\nBetween VT1 and VT2 (148-170 bpm): 10 x 0.05 = 0.5 hours/week\nAbove VT2 (> 170 bpm): 10 x 0.15 = 1.5 hours/week\nExample weekly plan:\n- 4-5 easy runs below VT1: 8 hours total\n- 1 tempo run at VT1-VT2: 30 minutes\n- 1 interval session above VT2: 1.5 hours (including warm-up/cool-down)
Result:8.0 hrs easy | 0.5 hrs tempo | 1.5 hrs high-intensity per week
Frequently Asked Questions
What is Ventilatory Threshold 1 (VT1) and what does it represent physiologically?
Ventilatory Threshold 1 (VT1), also known as the aerobic threshold or first ventilatory threshold, is the exercise intensity at which ventilation begins to increase disproportionately relative to oxygen consumption. Below VT1, breathing increases linearly with workload, but at VT1, the body begins producing more carbon dioxide from buffering the early accumulation of lactate with bicarbonate. This excess CO2 stimulates additional ventilation beyond what is needed for oxygen supply alone. VT1 typically occurs at 45 to 65 percent of VO2max in trained individuals and corresponds to blood lactate levels of approximately 1.5 to 2.5 mmol/L. It marks the upper boundary of the moderate exercise intensity domain.
References
Reviewed by Sher, Sports Science & Nutrition Specialist · Editorial policy