By sport
Ultra Running Training Zones
Aerobic durability dominates. Train mostly at MAF / Zone 2 by heart rate; pace is unreliable over big vert and long hours.
Max Heart Rate Calculator
Your maximum heart rate is the highest your heart can beat in all-out effort. Age formulas estimate it: Tanaka gives 208 − 0.7 × age; the classic 220 − age tends to run high. At age 35 that is roughly 184 and 185 bpm, but the real value varies by ±10–12 bpm, so test it to be sure.
Heart Rate Zone Calculator
Your heart-rate zones are percentages of your maximum heart rate: Zone 1 is 50–60%, Zone 2 60–70%, Zone 3 70–80%, Zone 4 80–90% and Zone 5 90–100%. At a max of 185 bpm, Zone 2, the key aerobic-base zone, runs about 111–130 bpm. Spend most easy training in Zones 1–2.
MAF 180 Formula Calculator
Maffetone's 180 Formula sets your maximum aerobic heart rate at 180 minus your age, adjusted for health and training status. A consistent, injury-free 35-year-old gets 180 − 35 = 145 bpm; the aerobic training range is then about 135–145 bpm. Train at or below it to build a strong, low-stress aerobic base.
Running Power Zones Calculator
Running power zones anchor to your running Critical Power (CP), not cycling FTP. The two are not interchangeable. Stryd's five-zone model runs Easy below 80% CP up to Repetition above 115%. At a running CP of 280 W, Threshold tops out at 280 W and Repetition is open-ended above about 322 W.
VDOT Calculator & Running Pace Zones
VDOT is Jack Daniels' single running-fitness number, combining VO₂max and running economy from one race result. A 5 km in 20:00 gives a VDOT of about 49.8. From that one number the model derives every training pace, Easy, Marathon, Threshold, Interval and Repetition, so all your zones come from a single race.