Sleep

Sleep is an active, organised process rather than simple rest. Across the night the brain cycles repeatedly through lighter sleep, deep sleep, also called slow-wave sleep, and rapid eye movement (REM) sleep, with each cycle lasting around ninety minutes. Deep sleep dominates the earlier part of the night and is when much of the body's physical restoration occurs, including the release of growth hormone and the repair of tissues. REM sleep becomes more prominent later in the night and is important for consolidating motor skills and memory, so the technique drilled in training is embedded partly while the athlete sleeps.

The functions of sleep read like a list of everything an athlete needs. Physical recovery and tissue repair, the restoration of energy stores, hormonal balance including the hormones that govern appetite, stress and muscle building, immune function that protects against infection, and the clearing of metabolic by-products all depend on adequate sleep. So does the brain, since reaction time, judgement, concentration, learning and mood are all shaped by how well someone has slept. Both the quantity and the quality of sleep matter, and losing either blunts these benefits. This is why sleep sits alongside training and nutrition as one of the pillars of recovery and adaptation, the process by which the body absorbs the work of training and comes back stronger.

Adults are generally advised to get between seven and nine hours of sleep, and many athletes need more rather than less, because of the physical and mental demands they place on themselves. Deliberately increasing sleep, sometimes called sleep extension, has been shown in some athlete studies to improve aspects of performance such as reaction time, accuracy and sprint speed, particularly where baseline sleep is insufficient, while short sleep does the opposite. A tired athlete is slower to react, makes poorer decisions, judges distances less well, and feels a given effort as harder than it is.

The link that matters most to the musculoskeletal (MSK) clinician is with injury. Chronic short sleep is associated with a higher rate of injury, with observational studies, especially in adolescent athletes, linking sleeping less than around eight hours a night to a greater likelihood of getting hurt. Poor sleep also raises the risk of illness and infection, slows recovery between sessions, and contributes to the fatigue and underperformance seen in overreaching. The reasons are not hard to see: an athlete who is not recovering fully, whose reactions and judgement are dulled, and whose tissues are repairing less effectively is more exposed to injury and less able to absorb training load. Sleep is therefore a genuinely modifiable injury risk factor, which is exactly why it belongs in any conversation about keeping athletes fit and available.

Most sleep difficulty in athletes comes down to too little opportunity or poor habits, but some points should prompt a closer look. Persistent insomnia, difficulty getting to sleep or staying asleep that continues despite sensible habits, is common and treatable and should not simply be endured. Loud snoring with witnessed pauses in breathing, choking or gasping at night, waking headaches, poor concentration, or waking unrefreshed after a full night raises the possibility of obstructive sleep apnoea (OSA), which needs assessment and referral. Excessive daytime sleepiness matters both for performance and for safety, particularly around driving. Sleep problems frequently travel with anxiety, low mood and other mental health difficulties, each worsening the other, so a sleep complaint is a chance to ask about wellbeing more broadly. Underperformance, recurrent illness or repeated injury against a background of chronic short sleep should also prompt a look at sleep as part of the wider assessment. Sleep disruption around travel and time-zone change, or from night competition, is predictable and worth planning for rather than leaving to chance.

The foundation of better sleep is good sleep habits, often called sleep hygiene. A regular sleep and wake time, held as far as possible around training and travel, steadies the body clock. The bedroom should be dark, quiet and cool, and kept for sleep. Screens and bright light in the hour before bed should be limited, as should caffeine from the afternoon onwards and alcohol in the evening, since alcohol fragments sleep even though it can help with falling asleep. A wind-down routine, and avoiding heavy meals or hard training too close to bedtime, all help. Beyond habits, simply making more time for sleep is one of the most effective steps an athlete can take, and a short early-afternoon nap of around twenty to thirty minutes can top up sleep without disrupting the coming night, as long as it is neither too long nor too late.

Some situations need more than habits. For travel across time zones, gradually shifting the sleep schedule, using light exposure at the right times, and considering short-term melatonin under appropriate clinical guidance can ease the adjustment in selected cases of jet lag, though melatonin should not be used as a routine recovery supplement. For persistent insomnia, cognitive behavioural therapy for insomnia (CBT-I) is the first-line treatment and is more effective and durable than sleeping tablets, and it is more than sleep hygiene alone, using techniques such as stimulus control, sleep restriction, relaxation and cognitive strategies. Sleeping tablets are not first-line and should be used cautiously, if at all, in athletes, given next-day sedation, dependence risk, driving safety and anti-doping considerations. Referral is appropriate when obstructive sleep apnoea is suspected, when insomnia persists despite sensible measures, or when a mental health difficulty needs support in its own right. The clinician's role is to ask about sleep, tackle the modifiable causes, and know when a sleep disorder or a mental health issue needs specialist input.

• •Consensus and review work in sports medicine recognises sleep as central to athlete recovery, performance, illness risk, mental wellbeing and injury risk.
• •General adult sleep duration guidance, from bodies such as national sleep foundations, informs the seven to nine hour target, with athletes often needing more.
• •National Health Service and NICE guidance on insomnia support sleep hygiene and cognitive behavioural therapy for insomnia (CBT-I) as first-line, with medication reserved and used cautiously.
• •British sleep societies and sports institute guidance inform the assessment of sleep disorders such as obstructive sleep apnoea and the practical management of travel and jet lag.

• •Sleep is an active process of physical recovery, hormonal restoration and skill consolidation, and both its amount and quality matter.
• •Deep sleep supports physical restoration and rapid eye movement sleep supports memory and motor learning, cycling through the night.
• •Most athletes need seven to nine hours or more, and sleep extension can improve reaction time, accuracy and speed where sleep is short.
• •Chronic short sleep, under around eight hours, is linked to higher injury and illness risk and impaired performance.
• •Snoring with witnessed pauses, unrefreshing sleep or excessive daytime sleepiness should prompt assessment for obstructive sleep apnoea.
• •Sleep hygiene and more sleep time are first-line, and cognitive behavioural therapy for insomnia is first-line for chronic insomnia.