At Blackberry Clinic our practitioners and doctors appreciate that there are many factors that may influence a successful outcome and return to full function following injury. A holistic view is taken of our patients lifestyle to determine the best route to recovery. With this in mind, Jordan, one of our physios at Blackberry Clinic Milton Keynes talks here about the importance of sleep.
What is sleep?
Sleep is a naturally reoccurring state of mind and body characterised by altering levels of consciousness in which we experience relatively reduced sensory activity, muscular activity and interactions with our surroundings. In humans, for the vast majority of us, we follow a daily pattern (usually at night) whereby sleep occurs in conjunction with our natural circadian rhythm, our unconscious internal time regulator.
Types of sleep
REM sleep (Rapid Eye Movement)
- This is the sub-period of sleep in which dreams are most associated – the body is able to temporarily paralyzed both upper and lower limbs during a “dream”. This is believed to be a protective mechanism utilised by the body to prevent self-harm and unnecessary energy expenditure.
NREM sleep (Non-Rapid Eye Movement)
- As the name suggests, this is the sub-period of sleep in which minimal/no eye movement occurs although dreaming can still occur in this phase. However some people may become ‘stuck’ in NREM and, as muscles are not paralyzed during this time, a person may experience what is commonly known as sleepwalking. This is usually more controlled in nature as unlike REM sleep, NREM associated dreams tend to that of more rational, controlled nature as opposed to hallucinatory and bizarre content found during REM sleep. This period of sleep consists of 3 stages – as you progress through these stages brain waves move to a lower frequency with the third and final stage of NREM sleep being your “deep sleep” phase.
Brief awakening
- There are huge variations to the intensity and duration of these peiods of brief awakening between the general population. For the majority of those not suffering from a sleep disturbance related disorder, awakenings during the night will not usually break the consciousness threshold, meaning when we wake up in the morning, we won’t have any recolection. These short periods occur primarily for repositioning purposes.
Sleep guidelines
- Newborns (0-3 months): Sleep range narrowed to 14-17 hours each day
- Infants (4-11 months): Sleep range widened two hours to 12-15 hours
- Toddlers (1-2 years): Sleep range widened by one hour to 11-14 hours
- Preschoolers (3-5): Sleep range widened by one hour to 10-13 hours
- School age children (6-13): Sleep range widened by one hour to 9-11 hours
- Teenagers (14-17): Sleep range widened by one hour to 8-10 hours
- Younger adults (18-25): Sleep range is 7-9 hours
- Adults (26-64): Sleep range did not change and remains 7-9 hours
- Older adults (65+): Sleep range is 7-8 hours
Sleep debt
Also known as sleep deficit, sleep debt refers to the amount of time lost due to lack of sleep. This often occurs as an accumulation over several days when an individual, much like a diet, does not meet their sleep requirements in relation to their daily activity levels.
Why do we sleep?
- Decreased energy demands; when we are sleeping, our metabolic expenditure is a fraction of that when awake due to multiple homeostasis related changes such as decreased brain function, heart rate, digestive processes and muscle activity.
- Information processing and synaptic plasticity; numerous studies have identified improved cognitive function such as increased memory recall and problem solving capabilities following subsequent sleep periods. This is often linked to events that have occurred during the day and other learned experiences.
- Restoration of key cellular components; well documented links between sleep, in particular NREM, and increased protein synthesis activity throughout the body. This ultimately allows for repair and growth of soft tissue. This is aided further by an increase in growth hormone production and secretion. A hormone that plays a crucial part in digestion, cell repair and regulation of other hormones.
To nap or not to nap?
Most people, in particular those with a demanding lifestyle, will experience spells of tiredness throughout the day. This will often result in reduced work output or alertness for example. Should you require a nap during the day, most commonly 12am-2pm, most studies suggest a time no greater than 30 minutes – excessively exceeding this time may result in the individual falling into stage 2 or 3 NREM for a prolonged period and subsequently wake up feeling unproductive and ‘groggy’.
Napping has recently been associated with a 37% lower coronary mortality, possibly due to reduced cardiovascular stress mediated by daytime sleep. Short naps at mid-day and mild evening exercise have been found to be effective for improved sleep, cognitive tasks, and mental health in elderly people.
Signs and symptoms of sleep deprivation:
- Difficulty falling asleep, including difficulty finding a comfortable sleeping position
- Waking during the night, being unable to return to sleep and waking up early
- Not able to focus on daily tasks, difficulty remembering
- Daytime sleepiness, irritability, depression or anxiety
- Feeling tired or having low energy during the day
- Trouble concentrating
- Being irritable, acting aggressive or impulsive
Strategies to improve sleep
- Sleep schedule – Ensuring that a regular schedule of meeting appropriate sleep time is met. It is recommended that you should try to avoid ‘lie ins’ during the weekend and instead stick to a more regular 10pm – 7am routine for example
- Activities – these can both aid or hinder an individual’s ability to fall asleep and remain in that state. Those individuals who regularly exercise throughout the week tend to sleep better. However, it’s important not to exercise too close to lights out due to sustained arousal and cognitive function post activity.
- Foods and substances – a number of foods have been found to disrupt sleep due to providing a stimulant like effect. These include those rich in nicotine and caffeine. Alcohol, although often seen to induce sleepiness initially, has been shown to massively impact the quality of the following sleep period, often fragmenting REM and NREM. The evidence for food and quantity of food/liquid consumption is mixed but the general consensus points towards eliminating large amounts shortly before attempting to sleep due to effortful metabolic reactions and increased need to urinate.
- Environment – it is usually recommended to adapt your sleeping environment into one that is quiet, as dark as possible as well as cool. The temperature aspect of this recommendation has been shown to vary quite substantially from person to person. Variations are also apparent in relation to mattress and pillows, however on average, a medium firm mattress and pillow provide the best global support, in particular for the spine.
- CBT – involves implementing various techniques such as relaxation techniques and finding underlying root causes of sleep insomnia and aims to tackle them directly.
It is evident that sleep plays a crucial role in not only general health, but also the management of musculoskeletal based injuries and conditions. It is paramount that sleep guidelines are met in conjunction with an appropriate rehabilitation programme to ensure optimal recovery. At Blackberry Clinic, we take a holistic approach with all patients ensuring that every aspect of their recovery is addressed and corrected accordingly.
Jordan Smith
Physiotherapist, Blackberry Clinic Milton Keynes
