Marathon runners, for example, are known to experience a euphoria and sense of oneness with nature during their grueling races. Persons participating in religious austerities such as corporal penance often come to take pleasure in their sufferings and can even experience an enlightening joy. Blood tests on people enduring these kinds of extreme duress have shown their endorphin levels to be several times normal.
比如馬拉松跑者在進行漫長艱辛的長跑中，會有心情高昂、與自然融為一體的幸福感；或者宗教苦行者遭受惡劣環境或肉體凌虐時，卻甘之如飴，甚至得到開悟的喜悅，此時當事人血液中的腦內啡 * 值都上升數倍以上。