Sussex Performance Centre

Why Sleep Is So Important For Weight Loss

A good night’s sleep is incredibly important for your health. It is just as important as eating healthy and training regularly.

So how does it impact weight loss? Did you know 8 hours of sleep correlates with a lower body mass index, lower levels of ghrelin (a hormone that suppresses appetite) and higher levels of leptin (a hormone that signals the body is full).

Sleep should be non-negotiable as it is that important to optimal health. It also is imperative for optimal performance and reaching your physical potential. It plays a huge role in you having a healthy hormonal system and is an obvious game changer if your goal is to lose body fat.

This is supported by science: people with short sleep duration tend to weigh significantly more than those who get adequate sleep. In fact, short sleep duration is one of the strongest risk factors for obesity.

In one extensive review study, children and adults with short sleep duration were 89% and 55% more likely to become obese, respectively.

What Happens When You Don’t Get Enough Sleep?

Suppressed testosterone production.

Testosterone production – go a few nights on 60% measures of sleep and see where your sex drive is at. Possibly a teenager or young man in his 20s won’t feel this, but wait until the 30s and 40s hit.

Increased cortisol release (the stress hormone).

When you are fatigued from a lack of sleep, the body requires an increase in cortisol to get it going and is also more insulin resistant (meaning it is much more likely to store glucose in the fat cells). You can see this yourself by the types of foods you look for when you are suffering from a lack of sleep – the type that provides quick energy but its generally calorie dense, adding to fat accumulation. Read about how stress makes you fat here.

Suppressed growth hormone production.

You release a lot of our HGH during certain cycles of sleep. This is extremely importantour health. HGH it plays a key role in growth, body composition, cell repair and metabolism.  HGH also boosts muscle growth, strength and exercise performance, while helping you recover from injury and disease. Science has shown that lower HGH levels may negatively impact your quality of life, increase your risk of disease and make you gain fat. This is one hormone you do not want to miss out on!

So How Do You Sleep Better?

Increase Bright Light Exposure During The Day

Your body has a natural time-keeping clock known as your circadian rhythm. It affects your brain, body and hormones, helping you stay awake and telling your body when it’s time to sleep. Natural sunlight or bright light during the day helps keep your circadian rhythm healthy. This improves daytime energy, as well as nighttime sleep quality and duration.

In people with insomnia, daytime bright light exposure improved sleep quality and duration. It also reduced the time it took to fall asleep by 83%. 

Reduce Blue Light Exposure in the Evening.

Exposure to light during the day is beneficial, but nighttime light exposure has the opposite effect. Again, this is due to its impact on your circadian rhythm, tricking your brain into thinking it is still daytime. This reduces hormones like melatonin, which help you relax and get deep sleep. Blue light, which electronic devices like smartphones and computers emit in large amounts, is the worst in this regard.

There are several popular methods you can use to reduce nighttime blue light exposure:

  • Wear glasses that block blue light.
  • Download an app such as f.lux to block blue light on your laptop or computer.
  • Install an app that blocks blue light on your smartphone. These are available for both iPhones and Android models.
  • Stop watching TV and turn off any bright lights two hours before heading to bed.

Try to Sleep and Wake at Consistent Times.

Your body’s circadian rhythm functions on a set loop, aligning itself with sunrise and sunset. Being consistent with your sleep and waking times can aid long-term sleep quality. Studies have highlighted that irregular sleep patterns can alter your circadian rhythm and levels of melatonin, which signal your brain to sleep.  If you struggle with sleep, try to get in the habit of waking up and going to bed at similar times. After several weeks, you may not even need an alarm.

Use Supplementation if You Follow Natural Sleeping Strategies.

  • Ginkgo biloba: A natural herb with many benefits, it may aid in sleep, relaxation and stress reduction, but the evidence is limited. Take 250 mg 30–60 minutes before bed.
  • Glycine: A few studies show that 3 grams of the amino acid glycine can improve sleep quality.
  • Valerian root: Several studies suggest that valerian can help you fall asleep and improve sleep quality. Take 500 mg before bed.
  • Magnesium: Responsible for over 600 reactions within your body, magnesium can improve relaxation and enhance sleep quality.
  • L-theanine: An amino acid, l-theanine can improve relaxation and sleep. Take 100–200 mg before bed.
  • Lavender: A powerful herb with many health benefits, lavender can induce a calming and sedentary effect to improve sleep. Take 80–160 mg containing 25–46% linalool.

Please note: make sure to only try these supplements one at a time. While they are no magic bullet for sleep issues, they can be useful when combined with other natural sleeping strategies.

Once sleep has been perfected, you will start to feel amazing and in turn will be able to train harder to achieve results.  Most notably, all other hormonal regulations will fall into place. The effect of sleep on weight loss and overall performance is pronounced so the most critical part of any training programme is to establish a correct sleep cycle. Through better sleep comes a better body and a better mind.

If you need a structured plan to improve your lifestyle, health, nutrition and fitness to get in the best shape of your life, speak to SPC about how we can help




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