Getting enough good-quality sleep can be difficult in today’s world. Modern lifestyles don’t always fit neatly with our body’s natural sleep-wake cycle. Artificial light, technology, work demands, shift patterns and busy social lives can all make it harder to get the sleep we need.
In the UK, 50% of people report they do not get enough sleep or suffer from insufficient sleep. There are many reasons why we may struggle to sleep well, including biological, technological and societal factors. Most adults need around 7–9 hours of sleep a night, but getting enough isn’t always as simple as going to bed a little earlier.
You may recognise some of these challenges yourself. Do you get home after a long day and find yourself doom-scrolling? The bright light from screens, along with the mental stimulation of scrolling, can make it harder for your body and mind to wind down for sleep. Or perhaps the lines between work and home life have become blurred, with emails and messages still demanding your attention in the evening. If you work shifts, irregular working hours can make it particularly difficult to maintain a consistent sleep routine and can disrupt your body’s circadian rhythm.
So, we know there are plenty of reasons why we don’t always get the sleep we need. But why is sleep so important? And what impact can it have on our health, fitness and wellbeing?
Why sleep is important for health
We have all had a bad night’s sleep. You get up in the morning and you’re feeling rough. Like you have had a big night out without the alcohol! Sleep is a biological necessity, and what you may not know is that it is just as significant as proper nutrition and exercise.
Sleep isn’t simply the body switching off. Different stages of sleep perform different functions, including memory processing, physical restoration and brain regulation. This is why being sedated isn’t the same as getting natural, restorative sleep. Substances such as alcohol and some sleeping medicines can make us drowsy or induce sleep, but they can alter the normal stages and processes of sleep that are important for physical and mental recovery.
During sleep, the body undergoes many processes that have an impact on our health. Some of the processes that occur during sleep include critical cellular repair, tissue growth, whilst supporting normal immune function. Sleep also plays a foundational role in cardiovascular health. During sleep, heart rate and blood pressure normally fall, giving the cardiovascular system a period of reduced demand. Insufficient or poor-quality sleep is associated with a higher risk of conditions including high blood pressure, diabetes, coronary heart disease (CHD) and stroke.
In addition to physical health, sleep is essential for cognitive function and brain health. Sleep helps consolidate memory, sharpen focus and improve decision making. It also plays an important role in metabolic health, helping the body regulate energy use, blood sugar and appetite. Poor sleep can disrupt these processes and may affect the hormones involved in hunger and fullness, potentially increasing appetite and cravings.
Sleep is therefore an important part of maintaining good physical health, metabolic health and positive mental wellbeing. It also plays a significant role in how we perform, recover and feel day to day.
Sleep and fitness
Muscle repair and growth
Tissue healing – Exercise places stress on your muscles, and sleep provides an important opportunity for the body to repair and adapt to that training
Protein synthesis – Poor sleep can reduce the body’s ability to recover and may negatively affect muscle protein synthesis and adaptation to training .
Energy restoration
Glycogen replenishment – Glycogen (stored glucose) is the energy source we predominantly use during high intensity workouts. Sleep allows your body to replenish these stores ready for your day.
Cellular energy – Sleep deprivation can affect how efficiently the body produces and uses energy, which can contribute to reduced endurance and make exercise feel harder.
Performance and Injury prevention
Injury reduction – Not getting enough sleep has a huge impact on injury risk. Research involving adolescent athletes aged 12–18 found that those who did not get the recommended amount of sleep were almost twice as likely to experience an athletic injury. While this research was conducted in young athletes, it highlights the potential importance of sleep for recovery, coordination and physical performance. Poor sleep can contribute to fatigue and slower reactions, which may affect exercise technique and increase the risk of injury.
Reaction time – Poor sleep can slow reaction time and affect coordination, concentration and decision-making — all of which matter when exercising or playing sport. Research involving Stamford University men’s basketball players found that extending sleep to around 10 hours per night improved sprint performance and increased shooting accuracy by 9%.
Hormones and metabolism
Sleep also interacts with hormones involved in appetite, stress and metabolism. Poor sleep can affect appetite regulation and may increase hunger and cravings, making it harder for some people to maintain their usual eating habits.
Sleep and mental wellbeing
Brain health and Cognitive function
Memory – Sleep plays an important role in learning and memory. During sleep, the brain processes and consolidates information gathered during the day, helping us retain what we’ve learned.
Decision making – Good-quality sleep can support attention, concentration, problem-solving and decision-making. When we’re tired, we’re more likely to struggle to focus and make mistakes.
Stress and toxin clearance – Sleep also plays an important role in managing stress. During sleep, levels of hormones such as cortisol and adrenaline can fall, helping the body and brain recover from the demands of the day. This is one reason why poor sleep can contribute to a cycle of increased stress and difficulty sleeping.
Sleep may also support the brain’s natural waste-clearance processes. The brain has a specialised system known as the glymphatic system, which helps remove metabolic waste from brain tissue. Research suggests that this process is more active during sleep, although scientists are still investigating exactly how it works and what this means for long-term brain health.
Emotional and resilience
Mood regulation – Sleep has a direct effect on your brain chemistry and can even alter it. Having adequate sleep allows the prefrontal cortex to better manage emotions, reducing irritability and stress.
Resilience – Getting enough good quality sleep has a direct relationship on emotional resilience by resetting your brain’s emotional control centers and sharpening your ability to cope with daily stress. Sleep deprivation severely lowers mental resilience by breaking down how the brain handles emotions, stress, and problem-solving. Chronic sleep problems are also associated with an increased risk of mental health conditions such as anxiety and depression.
5 Practical tips for better sleep
- Keep a consistent schedule
- Create a sleep-friendly environment
- Make your bedroom calm, comfortable, quiet and dark
- Keep bedroom temperature cool
- Use blackout curtains, sleep masks and earplugs if required
- Wind down away from screens
- Try switching off screens in the hour before bed – Bright light from screens can interfere with your body’s preparation for sleep.
- Read a book or listen to a podcast to unwind before sleep
- Make a calming routine that works for you
- Watch caffeine and alcohol
- Try switching to decaffeinated drinks in the afternoon – caffeine can remain in the body longer than you think and affect sleep
- Alcohol can make you feel sleepy and may help you fall asleep more quickly, but it can disrupt normal sleep patterns and reduce sleep quality later in the night
- Get daylight and movement during the day
- Getting outside during the day, particularly in the morning, exposes you to natural light, which helps regulate your circadian rhythm
- Regular physical activity can also support sleep, although vigorous exercise immediately before bed may not suit everyone.”
Sleep doesn’t have to be perfect
We can’t always control how well we sleep, and life doesn’t always follow a perfect routine. Work, family, stress, travel and other factors can all affect our sleep. Rather than aiming for perfect sleep every night, focus on the things you can control. A consistent routine, a sleep-friendly environment, regular movement and some time to wind down can all help.
Just like exercise and nutrition, small changes can add up. So tonight, why not try one simple change and see if it makes a difference?
