By sport
Rowing Training Zones
The Concept2 / British Rowing UT2–AN five-band model, anchored to 2k split and heart rate. Long aerobic UT2 is the base.
Max Heart Rate Calculator
Your maximum heart rate is the highest your heart can beat at all-out effort. Age formulas estimate it: Tanaka gives 208 − 0.7 × age, the classic 220 − age runs high. At age 35 that is 184 and 185 bpm, but true values vary by ±10–12 bpm, so test it.
Heart Rate Zone Calculator
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 aerobic-base zone, is 111–130 bpm. Most easy training belongs in Zones 1–2.
Karvonen Heart Rate Reserve Calculator
The Karvonen formula sets zones from your heart-rate reserve: maximum minus resting heart rate. Target = intensity% × (HRmax − RHR) + RHR. With a max of 185 and resting of 50 bpm (reserve 135), 70% gives 0.70 × 135 + 50 ≈ 145 bpm. The zones follow your fitness.
Rowing Heart Rate Zones (UT2–AN)
Rowing uses a five-band heart-rate model: UT2 is 55–70% of maximum, UT1 70–80%, AT 80–85%, TR 85–95% and AN above 95%. At a 190 bpm maximum, UT2 is 105–133 bpm and threshold AT 152–162 bpm. Most rowing volume should be steady UT2.
Daily Calorie Calculator
Your daily calorie need is your basal metabolic rate (BMR) multiplied by an activity factor, giving total daily energy expenditure (TDEE). A 35-year-old man, 70 kg and 175 cm, has a BMR near 1,624 kcal. Training at a moderate level (factor 1.55), he needs about 2,517 kcal a day to maintain weight.
Carbohydrate Intake Calculator
Fuel by duration. Under an hour, water is usually enough (0 g/h). From 1 to 2.5 hours, aim for about 60 g of carbohydrate per hour from a single source. Beyond 2.5 hours, you can absorb up to 90 g/h using a glucose-to-fructose mix near 2:1. A 2-hour session needs roughly 120 g total.
Sweat Rate Calculator
Your sweat rate is the fluid you lose per hour of exercise. Weigh yourself before and after a session, add any fluid you drank, and divide by the time. Lose 1 kg in an hour while drinking 500 ml and your sweat rate is 1.5 L/h. On long efforts, replace roughly 100% to 150% of it.
VO2max Estimator
VO2max is the most oxygen your body can use per minute, the ceiling on your aerobic fitness. The 12-minute Cooper test estimates it from distance: VO2max = (meters - 504.9) / 44.73. Run 2,400 meters and you score about 42 ml/kg/min, a recreationally active level. A lab test is more exact, but this gets you close.
BMI Calculator
BMI is your weight in kilograms divided by your height in meters squared. At 70 kg and 175 cm your BMI is 22.9, inside the healthy range of 18.5 to 24.9. It is a fast population screen, but it counts muscle as mass, so lean, muscular athletes often read high.