Stay Awake for 24 Hours
Make it through a full day and night without sleeping, then keep going until the 24-hour mark. It sounds simple, but sustained wakefulness becomes noticeably harder as the hours build: concentration drops, reaction times slow, mood can change and straightforward tasks start taking more effort than they normally would. The challenge is less about physical endurance than resisting your normal sleep cycle. Sleep deprivation is not harmless. Staying awake for 24 hours can significantly impair attention, judgement and coordination, so this should never be combined with driving, cycling in traffic, operating machinery, swimming alone or anything else where slower reactions could put you or somebody else at risk. It is also a poor choice for anyone whose health or medication could be affected by missed sleep. If you decide to complete it, treat it as a one-off challenge rather than something to repeat or build into a longer period without sleep. Choose a day when you have no safety-critical responsibilities, stay around other people if possible, and arrange to sleep afterwards rather than trying to carry on as normal. Stop early if you feel unwell, confused or unable to function safely.