The single activity we spend most of our time engaged in is sleeping. In fact on average we spend about eight hours a day (that’s 2,688 hours per year) sleeping, devoting around a third of our life to this one occupation. But what are the reasons for this and what impact does disturbed or deprived sleep play on our ability to perform physically?
Resting is only one reason why we sleep, as during this time we are in a transient state where we learn and process information, too. We need it so much that if we miss one night of sleep our body tries to recover what was lost during subsequent nights. Without sleep, we feel weak and dull, and underachieve both mentally and physically. However, feeling tired can feel normal after a short time, tricking us into thinking we are unaltered from previous states, when in actual fact we have physically and mentally dropped down a level.
Sleep cycles
We only begin to notice changes when we see that our cycling is beginning to be affected – maybe our performance times are going up, we can no longer stay with the chain gang on a Saturday ride, or we start to lose interest altogether and not go out on the bike. It is at this point when we need to consider what is happening to cause these changes. Usually the starting point is our sleep patterns.
Research has repeatedly shown that those who have disturbed sleep will incur negative effects on their alertness, mood and physical performance over time. There are several theories as to why we need sleep, ranging from the reorganisation and storage of information gained throughout the day, enabling the retention of memory and consolidation of information, to the release of key hormones and tissue restitution that aid in the recovery and adaptation processes our body requires after a busy day.
Quality as well as quantity counts
With the average daily sleep cycle lasting around 7-9 hours in adulthood, evidence would appear to suggest that deprived and disturbed sleep will alter our physiological status. However, duration is not the only characteristic of a good night’s sleep, as restfulness, which is indicated by relative movements, and latency, indicated by the time between lights out and the first stage of true sleep (which usually accounts for about 50% of total sleep), both also have an impact on the quality of sleep. Sweet dreams: a good night’s sleep will help ensure that your cycling performance doesn’t suffer
Investigating the effects of sleep disturbance on subsequent cycling performance, researchers have found that following different nights’ sleep, which included a partial sleep disturbance in the middle of the night, findings revealed that partial sleep had significant negative effects on both cardiovascular and respiratory measures during submaximal and maximal exercise. Others have suggested that such short-term disturbances, such as that encountered following a single night’s sleep, may have little if no physical effects, but impair mental functioning, which could have an indirect link to physical performance.
Lack of sleep affects cardiovascular performance
The principle that experts do agree on is the effect of accumulative sleep disturbances on our ability to undertake meaningful physical performance and to recover from and adapt to our cycling sessions. Evidence has pointed to the fact that we can expect to lose as much as 11 percent of our cardiovascular performance as a result of prolonged alternations in our sleep patterns. Studies show that 30-36 hours of sleep deprivation can result in such loss.
So if you need eight hours’ sleep a night yet only get six or you are continually restless throughout the night, you will accumulate enough sleep debt over a period of time that can significantly reduce your physical and mental performance, directly impacting on your cycling and recovery from sessions. It is generally thought that exercise promotes sleep, but often we introduce factors into our lives that have a negative effect rather than positive.
By minimising excess fluid intake, particularly caffeine and alcohol close to bedtime, eating evening meals at a regular time a few hours before resting the head, not undertaking strenuous exercise too late in the evening, ensuring that the sleeping environment is relaxing, avoiding television just before lights out and preventing mid-evening naps, you can optimise your chances of having an undisturbed 7-9 hours each night – recharging your batteries and benefiting from the essential recovery processes your body needs to go through.