What Does Sleep Do for You?
To continue with things we need to help improve our ability of changing our health, today we are looking at a topic that is often overlooked or not usually considered when most people look at exercising. A number of tasks vital to health and quality of life are linked to sleep, and these tasks are impaired when you are sleep deprived.
Learning, Memory, and Mood
Individuals who have trouble grasping new information or learning new skills are often advised to “sleep on it,” and that advice seems well founded. Recent studies reveal that people can learn a task better if they are well rested. They also can remember better what they learned if they get a good night’s sleep after learning the task than if they are sleep deprived.
Exactly what happens during sleep to improve our learning, memory, and insight isn’t known. Experts suspect, however, that while people sleep, they form or reinforce the pathways of brain cells needed to perform these tasks. This process may explain why sleep is needed for proper brain development in infants. Not only is a good night’s sleep required to form new learning (new exercises)and memory pathways in the brain, but sleep is also necessary for those pathways to work up to speed. Several studies show that lack of sleep causes thinking processes to slow down. Lack of sleep also makes it harder to focus and pay attention. Lack of sleep can make you more easily confused. Studies also find a lack of sleep leads to faulty decision making and more risk taking, a lack of sleep slows down your reaction time.
Even if you don’t have a mentally or physically challenging day ahead of you, you should still get enough sleep to put yourself in a good mood. Most people report being irritable, if not downright unhappy, when they lack sleep. People who chronically suffer from a lack of sleep, either because they do not spend enough time in bed or because they have an untreated sleep disorder, are at greater risk of developing depression.
Your Heart
Sleep gives your heart and vascular system a much-needed rest. During non-REM sleep, your heart rate and blood pressure progressively slow as you enter deeper sleep. During REM sleep, your heart rate and blood pressure have boosted spikes of activity. Overall, however, sleep reduces your heart rate and blood pressure by about 10 percent. If you don’t get enough sleep, this nightly dip in blood pressure, which appears to be important for good cardiovascular health, may not occur. According to several studies, if your blood pressure does not dip during sleep, you are more likely to be at risk of health issues such as chest pain known as angina and an irregular heartbeat.
A lack of sleep also puts your body under stress and may trigger the release of more adrenaline, cortisol, and other stress hormones during the day. These hormones contribute to your blood pressure not dipping during sleep, thereby increasing the risk for heart disease. Inadequate sleep may also negatively affect your heart and vascular system by the increased production of certain proteins thought to play a role in heart disease.
Some of the effects of too much cortisol in the body are:
• Our bodies become less able to use glucose for energy and thus blood sugar levels become elevated and these carbs get stored as fat. (Think weight gain, especially around the waist)
• There is a decrease of protein synthesis – you take longer to repair and recover.
• There is an increase protein breakdown, that is, muscle wasting – you experience a loss of both muscle tissue and training strength. (Remember last week we spoke about how more muscle = less body fat!)
• There is a loss of minerals which, over time, can lead to osteoporosis.
• Your immune system becomes compromised due to the shrinking of lymphatic tissue and the decrease of the number of lymphocytes. This is in turn, leaves you more susceptible to colds, flu and allergies.
Your Hormones
Deep sleep triggers more release of growth hormone, which fuels growth in children and boosts muscle mass (think about the fat burning effects of resistance training) and the repair of cells and tissues in children and adults. Your mother also probably was right if she told you that getting a good night’s sleep on a regular basis would help keep you from getting sick and help you get better if you do get sick. During sleep, your body creates more cytokines—cellular hormones that help the immune system fight various infections. Lack of sleep can reduce the ability to fight off common infections.
Evidence is growing that sleep is a powerful regulator of appetite, energy use, and weight control. During sleep, the body’s production of the appetite suppressor leptin increases, and the appetite stimulant grehlin decreases. Studies find that the less people sleep, the more likely they are to be overweight or obese and prefer eating foods that are higher in calories and carbohydrates. People who report an average total sleep time of 5 hours a night, for example, are much more likely to become obese compared to people who sleep 7–8 hours a night.
A number of hormones released during sleep also control the body’s use of energy. A distinct rise and fall of blood sugar levels during sleep appears to be linked to sleep stage. Not getting enough sleep overall or enough of each stage of sleep disrupts this pattern. One study found that, when healthy young men slept only 4 hours a night for 6 nights in a row, their insulin and blood sugar levels mimicked those seen in people who were developing diabetes. Another study found that women who slept less than 7 hours a night were more likely to develop diabetes over time than those who slept between 7 and 8 hours a night.
SLEEP
A review in 2010 suggested that exercise generally improves sleep for most people, and helps sleep disorders such as insomnia. The optimum time to exercise may be 4 to 8 hours before bedtime, though exercise at any time of day is beneficial, with the possible exception of heavy exercise taken shortly before bedtime, which may disturb sleep. According to a 2005 study, exercise is the most recommended alternative to sleeping pills for resolving insomnia. Exercise can be a healthy, safe and inexpensive way to achieve more and better sleep.
Effects of rest after resistance training
During a workout, intense lifting causes microscopic tears to form in the fibre and connective tissue of muscles. These tears fatigue the muscles and accumulate in large number. With proper sleep & rest before your next workout and, sufficient nutrients, the muscles are slowly rebuilt over the following days. Without proper rest the chances of results stopping or an injury occurring are increased. The ability of the body to rebuild its muscles also increases mass, strength and muscle capacity. The digestion of protein with our meals provides the raw material that can be used to develop new muscle. The soreness that occurs 24 to 72 hours or more after workouts was once believed to occur from the build up of lactic acid, which the muscles produce as they use energy, but it is now believed that the soreness is the direct result of muscle tearing. This soreness is known as delayed onset muscle soreness, or DOMS for short.
Just to remind you here are some of the Health benefits of resistance training
Physical and mental health benefits that can be achieved through resistance training include:
• improved muscle strength and tone – to protect your joints from injury. It also helps you maintain flexibility and balance and helps you remain independent as you age
• weight management and increased muscle-to-fat ratio – as you gain muscle, your body burns more kilojoules when at rest
• greater stamina – as you grow stronger, you won’t get tired as easily
• prevention or control of chronic conditions such as diabetes, heart disease, arthritis, back pain, depression and obesity
• pain management
• improved mobility and balance
• improved posture
• decreased risk of injury
• increased bone density and strength and reduced risk of osteoporosis
• improved sense of wellbeing – resistance training may boost your self-confidence, improve your body image and your mood
• a better night’s sleep and avoidance of insomnia
• increased self-esteem
• enhanced performance of everyday tasks.