The brain forces to conduct both responses simultaneously. Human beings are the only species capable of laughter, and the average adult does so approximately 17 times per day. Good health is one of the many benefits of laughter. Laughter reduces our stress levels by reducing the level of stress hormones, and also helps us cope with serious illnesses. Physiologically, laughter promotes healing, by lowering the blood pressure, and by increasing the vascular blood flow and the oxygenation of the blood.
Physical fitness stemming from laughter is a benefit known to few.
Scientists estimate that laughing 100 times is equivalent to a 10-minute workout on a rowing machine, or to 15 minutes on a stationary exercise bike. The mere act of laughing exercises the diaphragm, as well as the abdominal, respiratory, facial, leg, and back muscles. Another benefit of laughter is that it improves our over-all mental health. Pent up negative emotions, such as anger, fear, and sadness, can cause biochemical changes in our bodies that can produce a harmful effect. Laughter provides a harmless outlet for these negative emotions, and provides a coping mechanism for dealing with difficult or stressful situations.