Sleep by Nick Littlehales

Nick Littlehales argues that the standard advice to get 8 hours a night sets people up to fail, because it makes every imperfect night a failure and feeds the anxiety that keeps people awake. His alternative, the R90 method, asks you to stop counting hours per night and start managing sleep cycles across a week.

The framework uses the roughly 90-minute sleep cycle as the unit. You fix a wake time first, then count backwards in 90-minute blocks to a bedtime, aiming for a weekly total — around 35 cycles for most people — with the understanding that individual nights will vary and a shortfall can be recovered across the week. Around that sit several other elements: identifying whether you lean early or late as a chronotype and scheduling accordingly; controlled recovery periods, meaning a short nap of about 20 to 30 minutes or a full cycle taken in the early afternoon or early evening; deliberate pre-sleep and post-sleep routines; and attention to the sleep surface, bedroom temperature, light and what you do in the 90 minutes either side of sleep. Later chapters apply this to travel, training load and competition.

It is aimed at athletes, people with irregular or demanding schedules, and anyone for whom a rigid 8-hour target has become a source of stress.

On the evidence: several components align with sleep science. A consistent wake time is one of the better-supported behavioural levers, short afternoon naps do improve alertness, and reducing the pressure placed on any single night is therapeutically sensible. The weak point is the cycle itself. Sleep cycles are not reliably 90 minutes — they vary between individuals and lengthen or shorten across the night — so scheduling in exact 90-minute blocks is a useful approximation, not a physiological rule. The R90 programme as a package has not been tested in controlled trials. Chronic insomnia or suspected sleep apnoea needs clinical assessment rather than a scheduling system.