MET Level: Sexual activity averages around 2 to 3 METs during foreplay, 3 to 4 METs during orgasm, and can peak up to 6 METs or more during active coitus. A 6 MET level classifies the peak exertion as moderate-to-vigorous physical activity.Calorie Burn: Intercourse typically burns about 101 kcal for men and 69 kcal for women per session, depending on duration and vigor.Heart Rate: Mean heart rates during sex range from 90 to 130 beats per minute, with brief peak spikes up to 170 beats per minute during climax.