The only mammal that delays sleep willingly is man. Self-imposed sleep deprivation is also the main reason behind extreme drowsiness.
Working out not only reduces stress, but also helps in improving sleep quality. The best exercises for a better sleep include aerobics, strength training and yoga.
Sleeping at higher altitudes takes some getting used to. Reduced oxygen levels disrupt sleep and it takes two to three weeks for people new to higher altitudes adjust to the new environment.
Ideal sleeping hours differ for people based on their age. An infant needs to nap for 12-17 hours, a toddler needs 11-14 hours and the optimum duration for adults is 7-9 hours.
On an average humans sleep eight hours a day, which is one-third of the day. By extension, we spend one-third of our life sleeping.