Training Resources

Learn how temperature, humidity, light, timing, preparation, nutrition, and readiness affect workout performance, comfort, and injury risk.

Learn how sleep, nutrition, hydration, rest, active recovery, supplements, sauna, and cold plunges affect recovery after a workout.

Understand resting heart rate, HRV, heart rate recovery, zones, max heart rate, sleeping heart rate, thresholds, and cardiac drift.

A practical guide to heart rate zones, max heart rate estimates, heart rate reserve calculations, and workout intensity categories.

Explore five complementary pillars of exercise for longevity: strength, aerobic fitness, high-intensity fitness, mobility, and balance.

Compare the Fox, Tanaka, Gellish, Nes, Gulati, and Inbar formulas for estimating maximum heart rate and learn when measured max HR is more useful.

A table with the estimated maximum heart rate by age according to the Fox, Tanaka, Gellish, Gulati, Inbar, and Nes formulas.

Use the MET calorie formula to estimate total and active calories burned from your weight and workout duration, with examples, a table, and accuracy limits.

A simple guide to VO2 max, cardio fitness, lab tests, wearable estimates, training methods, benefits, and limitations.

Learn how the Norwegian 4x4 interval protocol works, why it is popular, how to pace each interval, and how it can improve VO2 max.