In today’s interview I get to speak with sleep scientist, Dr Amy Bender, about the importance of getting enough good quality sleep for our health and ability to recover.
Amy is very passionate about sleep deprivation and sleep restriction and how it affects us. Being an athlete herself, she is interested in the vital role sleep plays in athletic training, performance and recovery science.
In today’s interview we also get a chance to talk about the three main things we should consider when thinking about good sleep and the main factors impacting our sleep quality and quantity.
If you know someone who is interested in learning more about how sleep affects them, what they can do to improve sleep, or are unsure if they are getting enough good quality sleep, this interview is for them.
I enjoyed this interview as I have been tracking my own sleep using the Oura ring (you can read my interview with Oura ring CEO here and read why I rate the Oura ring as my number one sleep tracker here) and have noticed how a good night’s sleep can really set me up for the day. Naturally, I have developed a keen interest in what I can do to improve the quality of sleep I’m getting.
After speaking with Amy, I have a better understanding of what changes I can make to my routine to ensure I am getting the most restful and restoring sleep possible.
Special thanks to Amy for joining me on the show. Enjoy the episode!
Show Notes with Timestamp Links
Highlights of what we talk about during the interview:
Click on one of the timestamp links in the brackets to jump to that point in the interview audio.
[00:20] – Introducing Dr Amy Bender, who has a PhD and M.Sc degrees in experimental psychology from the Washington State University, specialising in sleep EEG. She developed sleep intervention protocols for numerous Canadian national sport teams.
[01:12] – Sleep falls into the realm of recovery science; is this a neglected area of science? There is an increasing interest in sleep, and athletes and sports teams are starting to take an interest in how quality sleep affects performance.
[02:48] – Amy explains that sleep deprivation means going completely without sleep, such as, in cases when pulling an all-nighter. More realistic studies look at sleep restriction, which is much more common. This happens when we go to bed later/wake up earlier and get less than the ideal amount of sleep. When thinking about improving sleep we should consider three factors: 1. Quantity, the amount of sleep across a 24-hour day; 2. Quality, e.g. are we waking up during the night; and 3. Timing, aligning to your preferred chronotype.
[05:04] – With sleep restriction, sleep debt can build up over the week resulting in people trying to catch up on the lost sleep over the weekend. What we then see is a large variability in sleep during the week vs weekend – this effect is called social jet lag. The larger the variability, the more social jet lag and the more likely it is that people will experience depression and performance issues. (ref)
[06:47] – Amy explains that polyphasic sleep is a myth and that, even though we should always try to get the best quality, quantity, and timing of sleep, there are times when we need to be flexible as life can sometimes be unpredictable. She also explains how to think in terms of weekly sleep need.
[10:29] – The time it takes to recover from sleep deprivation can depend on what you are doing during that period of sleep deprivation. Taking caffeine or being exposed to bright light at night, for example, will suppress melatonin and decrease sleep quality affecting the ability to recover.
[12:26] – Age is another big factor. Teenagers as well as athletes need more hours of sleep (8-10 hrs), than normal adults (7-9 hrs) and adults of 65+ years of age (7-8 hrs). Amy explains how athletes need more sleep time to recover from training and how teams are starting to look at that information and incorporate it into their training strategies.
[16:42] – Amy shares some examples of data that could be used for recommendations from studies they did looking at how athletes recover from jet lag. We also discuss how the US Winter olympic ski jumpers were purposely arriving at the competition events jet lagged and how that approach worked out for them.
(Biohackers Lab Tip: Listen to veteran flight attendant Christopher Babayode explain how he beats jet lag)
[20:20] – How can we tell we are getting enough sleep? Getting up without an alarm clock is a good sign that you are getting enough quantity, quality, and timing of sleep. Other good sings include not needing assistance (e.g. caffeine) to keep awake, feeling alert and having consistent sleep/wake up times across the week.
[21:27] – Using data from Fitbit, which was looking at bedtime consistency, Amy explains why not varying your bedtime and wake time by more than an hour is good advice. Your body has a rhythm and it knows when it should be sleeping and when it should be awake; having a consistent schedule is beneficial for good sleep and keeps you more in line with your melatonin release.
[24:40] – When people are trying to improve sleep, many talk about sleep supplements like melatonin, but the basic starting point for good sleep should be getting the bedtime and wake time right. People should also consider some basic sleep hygiene tips such as putting away electronic devices, avoiding caffeine after noon, and not drinking alcohol before bed to try and get better quality sleep.
[26:10] – How will melatonin secretion be affected by blue light? Melatonin is typically released two hours before normal bedtime and light exposure can impact your melatonin by suppressing it, as well as delaying its release. Amy explains how light is the number one cue for the circadian clock because our circadian clocks are not exactly on a 24-hour cycle.
[29:44] – The type of device and the type of activity you are doing on that device both matter. How close is it to your eye? How bright is it? How stimulating is the interaction? Many variables impact how much it affects you. Amy recommends putting away all electronic devices at least an hour before bedtime and not having a TV in the bedroom. Instead, she recommends relaxing activities such as a warm bath, reading from a paper book, breathing, stretching or writing a to-do list.
[35:11] – It is not just the act of reading something, it is the paper quality that calms you, puts you in the parasympathetic state and we can see the effect in as little as 6 minutes. Amy shares her nighttime routine; even though she currently isn’t using sleep tracking devices she sets a bedtime alarm an hour before bed to remind her to start preparing for sleep.
[38:43] – How would someone know what their natural body clock is? Working this out can be challenging. During a vacation period where we don’t have any constraints and aren’t taking other stimuli we can pay attention to when we feel sleepy at night and when we wake up. This can give us an idea of our natural rhythm. Regardless, we can use light to entrain ourselves to different cycles.
[41:33] – Research says 15% of the people are morning types, 15% are evening types and the rest are somewhere in the middle. People interested to see where they might fall on the scale should look up the Morningness-Eveningness Questionnaire.
[43:00] – The circadian rhythm and sleep pressure or homeostatic pressure are the two main processes that regulate sleep. The longer you are awake, the higher the pressure for sleep; this is why napping during the day reduces some of the pressure. Homeostatic pressure is based on prior sleep-wake activity and the circadian system is independent of it. The longer we stay awake the more deep sleep we are going to have.
[48:53] – Sleep restriction results in more deep sleep but purposely sleep restricting ourselves in order to get more deep sleep is not recommended. There are other things we can do to try and achieve more deep sleep, including getting a firmer mattress or mattress that wicks heat away and exercising.
[50:14] – When is the best time to exercise? Temperature drops when we go to sleep, but exercise elevates it back up and also kicks in certain hormones, as well as adrenaline, all of which can be quite disruptive to sleep. Ideally, we should avoid exercise three hours before bedtime. Evening types, however, get a better workout later in the day, so if they can get away with it, they should also delay bedtime to compensate – admittedly, work commitments can often make this a challenge.
[53:28] – Is getting a large amount of deep sleep a good indicator of quality of sleep? There is a lot of variability with how much deep sleep individuals are getting and some of it can be down to genetics so comparatively it is not the best marker. Individuals can use deep sleep, however, to track themselves and see how different variables affect their personal deep sleep e.g. how does exercise, alcohol, or fibre affect my personal deep sleep quantity?
[55:44] – So, how do we quantify sleep quality? Subjective questions such as: “How do you feel about and are you satisfied with the quality of your sleep?”, can give us a good idea about the quality of sleep a person is getting. There are also more objective measures. The National Sleep Foundation came up with guidelines to answer that question. You should be falling asleep in less than 30 minutes, time in bed should be 85% sleep time, and you shouldn’t be waking up more than once per night and for no more than 20 min.
[57:19] – Gary’s Oura ring sometimes indicates “awake” times even though he is not consciously aware of this, how can this be? Amy explains how everyone wakes up multiple times during the night without remembering it. This happens during the transitioning from different stages of sleep. It is only waking up and remembering it that is harmful. We also discuss sleepwalking and how this affects the quality of sleep.
[1:02:07] – Finally, we discuss how Mediterranean countries tend to have siestas and napping during the day due to the heat, but they also tend to stay up later. How does it affect them?
[1:04:02] – To follow Amy and find out more on her work, go to the Centre for Sleep and Human Performance website where she currently works and also find her on Twitter and Instagram @sleep4sport She also suggests athletes and coaches, or teams keep an eye out for the Athlete Sleep Screening Questionnaire which will be published soon on the centre’s website.