How much sleep do you need? What the evidence says for adults who train

Adults need seven hours or more of sleep a night on a regular basis, and seven to nine hours suits most people. That is the joint consensus of the American Academy of Sleep Medicine and the Sleep Research Society. For people who train, sleep is part of the programme: it is when much of the recovery the workout asked for actually happens.

TL;DR

• Target 7 to 9 hours. Under 7 hours, night after night, is short sleep.
• A regular wake time, seven days a week, is the single most useful habit.
• After a short night, keep training moderate rather than skipping it or going all out.
• Use the sleep calculator to find a bedtime that fits your alarm.

What do the guidelines actually say?

In 2015, the American Academy of Sleep Medicine and the Sleep Research Society published a joint consensus after a panel reviewed the evidence on sleep duration and health. Their recommendation for adults aged 18 to 60 was seven or more hours per night on a regular basis. They found that regularly sleeping less is associated with weight gain, diabetes, high blood pressure, heart disease, depression, impaired immune function, more pain, worse performance and more errors.

The US National Sleep Foundation's expert panel reached a similar range in the same year: seven to nine hours for younger adults and adults, and seven to eight hours for people over 65.

Both are about adults in general. Individual need varies, and the best test is simple: how you feel and function during the day when you sleep your usual amount.

Why does sleep matter for training?

Training is a stress; adaptation happens in recovery. Short sleep makes the same session feel harder, makes it harder to hold a pace or a load, and is associated with more injuries and illness in athletes. It also makes appetite harder to manage, which matters if your goal is fat loss.

In practice that means:

• A run at your usual pace will feel harder after a five-hour night.
• Your strength may be down a little, and your focus noticeably.
• The risk of a sloppy rep or a missed step goes up.

What should I do after a bad night?

One short night is not a crisis. A sensible rule, and the one the revns planner uses:

• Sleep under your floor last night: keep today moderate. Do the session at an easier effort, or swap intervals for an easy run.
• Two or three short nights: plan an easier day and protect tonight's bedtime.
• Very long sleep: if you regularly need far more than nine hours, check in with how you feel and consider whether you are run down.

You can see this in your own data: log sleep in hours and the sleep tracking view shows your seven-day average next to your training.

How do I actually get more sleep?

The changes with the best return, in order:

1. Fix your wake time. The same time every day, including weekends, within about 30 minutes.
2. Count back 7.5 to 9 hours plus about 15 minutes to fall asleep. That is your bedtime. The sleep calculator does the arithmetic.
3. Daylight early, dim light late. Get outside in the morning; lower the lights and screens in the last hour.
4. Caffeine curfew. Caffeine stays in the body for hours. Stop roughly eight hours before bed if you are sensitive.
5. Finish hard training and big meals a couple of hours before bed when you can.
6. Keep the room cool, dark and quiet.

Do sleep cycles matter?

Sleep runs in cycles of roughly 90 minutes, though they vary between about 70 and 120 minutes. Waking at the end of a cycle can feel easier than waking in deep sleep, which is why the sleep calculator suggests bedtimes in 90-minute steps. Treat it as a guide; total sleep and a regular schedule matter more than hitting a cycle exactly.

Do naps count?

A short nap can help after a short night, and many athletes use them in heavy training blocks. Keep naps to about 20 to 30 minutes and earlier in the afternoon, so they do not push back your bedtime. A nap adds to your total for the day, but it does not replace a regular night: if you need a long nap every day to function, look at your night-time sleep first, and mention it to a clinician if it persists.

Should I track sleep?

Tracking helps if it changes what you do. Log the hours (a watch, a ring or your own estimate is fine), look at the seven-day average rather than single nights, and connect it to your training. If your average is under seven hours, the most effective training change you can make this month may be going to bed earlier.

When should I see a professional?

Talk to a clinician if you snore loudly with pauses in breathing or gasping, feel sleepy enough to nod off while driving or working, have insomnia most nights for several weeks, or have restless, uncomfortable legs at night. These are common, treatable problems, not things to fix with an app.

How does sleep change with age?

Need changes across life. The National Sleep Foundation's panel recommends 7 to 9 hours for younger adults and adults, and 7 to 8 hours for people over 65. Older adults often find sleep lighter and more broken, and wake earlier. That is common, but persistent poor sleep at any age is worth discussing with a clinician rather than accepting.

What about shift work and travel?

Shift work and long-haul travel push sleep away from the body clock, the circadian rhythm. A few habits help:

• Anchor what you can. Keep the same sleep window on consecutive shifts where possible.
• Light is the lever. Bright light when you need to be alert, darkness when you need to sleep: blackout blinds and an eye mask for daytime sleep.
• Plan training around sleep, not the other way around. After a night shift, a short, easy session beats a hard one.
• Across time zones, get daylight at the new morning and shift meals to local time.

Does alcohol help you sleep?

It can make falling asleep easier, but it fragments sleep later in the night and reduces sleep quality, which is why a night after drinking often feels unrefreshing. If you track resting heart rate or HRV, you will often see them worsen after alcohol. For training, the practical rule is simple: the night before a hard session or a race, skip it.

How does exercise affect sleep?

Regular exercise generally helps people fall asleep faster and sleep more deeply. Hard training very close to bedtime keeps some people awake, so if that happens to you, move intense sessions earlier and keep the last hour before bed calm. Easy movement, stretching or a walk in the evening rarely causes problems.

A simple sleep reset for the next two weeks

1. Pick a wake time you can keep seven days a week.
2. Set a bedtime 8 hours before it, and an alarm an hour earlier to start winding down.
3. Daylight within an hour of waking, even for ten minutes.
4. Caffeine only before early afternoon.
5. Log your hours each morning and look at the 7-day average, not single nights.

How do I know if I am getting enough?

Simple checks are more useful than any score:

• You wake around the same time without feeling dragged out of bed most days.
• You are not relying on caffeine to get through the morning.
• You do not fall asleep within minutes whenever you sit still in the afternoon.
• Your training feels normal for the effort you are putting in.

If you fail most of these, you probably need more sleep, a more regular schedule, or a conversation with a clinician about sleep quality. A week of logging bedtime, wake time and how you feel makes that conversation far more useful.

What should I log?

Hours slept, a 1 to 5 recovery rating each morning, and if you have a device, resting heart rate. Together they show whether short sleep is a pattern or a one-off, and they let the week plan keep hard sessions away from your worst nights.

Should I train after a terrible night?

Usually, yes, but adjust. A light or moderate session often makes people feel better and helps the next night's sleep. Skip maximal lifts, races and hard intervals after very little sleep, when coordination and judgement are worse. If you feel unwell, dizzy or unusually breathless, rest instead.

Keep notes simple: hours, a recovery rating, and anything unusual such as late caffeine or travel.

Related

• Sleep calculator
• Sleep and recovery tracking
• Menopause exercise: strength, sleep and bone health
• Zone 2 training explained
• What is HRV? Heart rate variability explained

This is general training guidance, not medical advice.

Sources

• Watson NF et al. Recommended Amount of Sleep for a Healthy Adult: A Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society. J Clin Sleep Med 2015
• Hirshkowitz M et al. National Sleep Foundation's sleep time duration recommendations: methodology and results summary. Sleep Health 2015