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Can Lack Of Sleep Cause Weight Gain or Limit Your Weight Loss and Strength Gains?

Updated: Nov 5, 2021

Short answer: Yes.

That is probably not the answer you were hoping for but it is the truth!

So how does is cause weight gain/ limit weight loss?

When you are in a state of sleep deprivation (from stress and blue light exposure) your body automatically switches to the sympathetic nervous system (SNS), this is your “fight or flight”. Back in our cave man days when we tapped into our SNS it was typically for short periods of time like when we were getting chased by animals. It was a survival instinct, and it was short term.

Now we deal with our bodies being in a CHRONIC SNS heightened state.

Our body basically goes into a type of survival mode. Heart rate and breathing rate are elevated, cortisol levels in our body increase, blood pressure stays elevated, the immune system drops, blood is redistributed to areas the body thinks is more important (away from organs which means there is less oxygen and nutrients going to them = poor organ health) and our body thinks we need to store and conserve energy for the future. The body can not differentiate what the stress is - it just knows that the SNS is elevated. Therefore our body will not only try to conserve energy making it hard to lose weight, it may even result in weight gain and diminished strength gains.

All this leads to chronic conditions such as hypertension, diabetes, and cardiovascular disease.

How Do You Improve Sleep?

Ok so now that you know sleep is important how do you improve it? Here are a few strategies which will not only decrease feelings of stress/anxiety/depression, but also improve sleep quantity and quality and overall health and well-being (including healthy body composition).

1) Try to tap into your parasympathetic nervous system (PNS) – the “rest and digest” section – regularly during the day. We want to bring down our heart rate, breathing rate, blood pressure and feelings of stress. Think about taking a few minutes during the day to focus on slow breathing, closing the eyes, getting a little bit of fresh air etc. Imagine if you spent all day tapped into a more SNS heightened state. Your body never gets the opportunity to relax and some of you will have to actively make time for it. If you are always more SNS dominant your body will have a hard time winding down for bed because it literally does not know how.

2) Bed time routine. I am sure you have all heard this before but having a regular night time routine can help. Our bodies LOVE routine. So try going to bed around the same time every night, doing similar things before bed etc. Things that will help tap into the PNS. What are those things? Keep reading!

3) Lower the temperature! That’s right when the temperature is lower our body will naturally slow down our heart rates and breathing rates and tap into the PNS. So think about lowering the temperature a couple degrees a couple hours before bed.

4) Reduce blue light exposure before bed. Blue light messes with our bodies ability to produce melatonin – that is the hormone responsible for making your feel sleepy. Blue light tricks your body into thinking it is still daytime. Blue light comes from things like cell phones, screens etc. So try dimming the lights (some people like using candles or salt lamps to dim the room) a couple hours before bed as well as decreasing screen time.

5) Make you bedroom only a place for sleep - this way when you go into your bedroom your brain only associates that space for sleep. Try avoiding checking your emails and social media in bed, watching television in bed, doing homework in your bedroom etc. You want to make it a calm space where your body will unconsciously go into a parasympathic state.

6) Make it dark! Use black our curtains if you need. Cover any little lights from electronics in your room with tape. The darker the room, the easier it is for your body to fall asleep and stay asleep.

7) Meal Time. This is one is a little more controversial, but I find that I do not sleep well if I eat too close to bedtime. It personally makes me feel uncomfortable and I find it hard to sleep when I can feel my body digesting food. Other people seem to have no problem with it so play around with this one and see how you feel. Your body’s circadian rhythm appears to intimately be related with your gut. So, when you eat around similar mealtimes regularly your body has some sort of ability to associate what time of day it is. For example, I am not a breakfast person, I very rarely eat breakfast. I just drink my coffee and away I go until I eat around 11am. If I do end up eating in the morning my whole day seems off. If I eat at 8am I think that my body thinks it is 11am. So, I am off my 3 hours. I get hungry for supper time 3 hours too early. I get tired earlier in the day. So instead of thinking my workday is done at 5/6 my body goes into end of day mode around 2/3. By the time bedtime rolls around I am a complete zombie. So, this is something I suggest you pay attention to. Write what time you eat and when you get tired and see if you meals times are consistent!

8) Caffeine intake. Avoid drinking anything with caffeine after 2pm. The half-life of caffeine is much longer than you think and can circulate in your body for hours after consumption.

9) Weighted Blankets. These bad boys are great for our nervous system. It is like someone is giving you a hug the entire time. It stimulates our parasympathetic nervous system to tap into your “rest and digest” side. This will also help decrease cortisol levels so that your melatonin levels can go up = better quality sleep!

10) Carb Timing. When you have carbohydrates our insulin levels increase. When there is an increase in insulin our cortisol levels will go down. When cortisol is lower our melatonin goes up making us feel tired (think about carb heavy holiday meals - yummy potatoes!). So you can try to have more of your carbs later in the day instead of earlier to try and adjust your body's cortisol curve to be lower in the evening! This is not a freebie to stuff yourself with more food than you naturally would though haha!

Sleep is Important!

When it comes to sleep – it is very under-rated and probably one of the most important things to consider when it comes to weight loss and health in general. I ask every single one of my clients (personal training or osteopathy) about their sleep because it affected so many systems in the body. It affects hormones and blood flow and so much more. If you have poor sleep habits or struggle with sleep, try tackling one item on the list at a time per week. Start off small. See which approaches work best for you. This is another habit change so be patient with yourself and give it time. It will be a process and that is ok!

If you are a regular exerciser and are not getting enough sleep it is important to modify your program and techniques and training styles because your body will just respond to it as another stressor. It cannot differentiate a good stress from a bad stress. So if you have trouble with sleep, have plateaued in your pursuit of strength, hypertrophy or weight loss and think you might need some help adjusting please do not hesitate to reach out! We’ve all been there and sometimes all you need is someone to turn you in the right direction!

Want to talk more about sleep? Feel free to reach out!

Until next time,

Stephanie Fusnik

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