The orgasmic spasm lasts a few seconds to a minute at the most, but is accompanied by intense physiological activity. Genitals swell with blood, the pulse races, muscles contract involuntarily. Some people's mouths open. Others' faces contort. Many women's toes curl. In men, big toes often stiffen as their little toes twist. Both partners' feet may arch and shake. Sweat typically surfaces on both participants' brows, the heart pumps frantically, and breathing becomes fast and shallow. Both partners' nostrils may flare and seem to heat the air as it surges through them. With climax, each partner is clenched by contractions at consistent 0.8 second intervals. The human sexual summit is a paroxysm of pleasure. A warm glow envelops the waist and chest. The toes relax.

The emotions, too, generally go into a seismic convulsion. For attempting, or pretending to attempt, to add to the species, both parties have received their reward. A mist of goodwill, wellbeing and lazy relaxation temporarily obscures reality. Both men and women may laugh or cry, or become uncommonly ticklish, although all these reactions are less common for men on the basis that they tend to show their feelings less anyway. Both sexes may experience a burst of creative thought since orgasm produces a near lightning storm in the right, creative-thinking side of the brain. Biological duty fulfilled, there normally follows a lengthy period of exhaustion, rest, and - frequently - sleep.