Health, Podcast, Recovery

Sleep – the foundation of health and performance with Dr. Charles Samuels | EP#216

 January 13, 2020

By  Mikael Eriksson

Sleep - the foundation of health and performance with Dr. Charles Samuels | EP#216

TTS216 - Sleep - the foundation of health and performance with Dr. Charles Samuels

Dr. Charles Samuels is the Medical Director of the Centre for Sleep & Human Performance in Calgary, Alberta. One of his key interest areas is exploring the relationship of sleep on recovery and performance in elite Canadian athletes, up to the Olympic level. In this episode, Dr. Samuels filters through some of the noise surrounding sleep, gives practical advice for getting adequate sleep, and discusses why sleep tracking wearables do more harm than good.

Discuss this episode!

  • Let's discuss this episode and the topic in general. Post any comments or questions in the comments at the bottom of the shownotes. Join the discussion here!

In this Episode you'll learn about:

  • The Athlete Sleep Screening Questionnaire. 
  • Differences between athletes and the general population in sleep patterns and sleep requirements. 
  • Why wearables and sleep trackers do more harm than good for our sleep. 
  • The case for catching up on sleep or banking sleep, and shooting for a weekly sleep goal. 
  • Caffeine. napping and chronotypes. 

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About Dr Charles Samuels

05:31 - 

  • I'm a sleep physician with a speciality in sleep medicine. 
  • I practice this clinically and I'm the medical director for the Centre for Sleep and Human Performance in Calgary. 
  • I have dual appointments at the University of Calgary and the Faculty of Medicine and Kinesiology because my areas of interest in research are:

    The relationship to sleep and recovery in high performance individuals. 

    The first domain was in law enforcement - looking at how shift work affects them. 
  • The other was with the Faculty of Kinesiology at the University of Calgary looking at the effects of sleep in athletes who are becoming over-trained. 

    These were National team and Olympic team athletes, mostly swimmers and cross-country skiiers. 
  • This transitioned into over a 10 year project of research looking at the relationship of sleep to recovery in elite athletes. 

Development of the Athlete Sleep Screening Questionnaire

06:43 -

  • In 2005 the clinicians I was working with were seeing more and more athletes falling off the curve. 

    This would be swimmers, cross country skiiers and sometimes long-track speed skaters - endurance related sports. 

    They wouldn't find any medical problems but they were becoming overtrained. 
  • There was a lot of work going on research wise with the physiologists, particularly Dr Dave Smith. 
  • They knew sleep was important and they knew me so I got involved. 
  • Prior to the 2006 Olympics I was in a meeting with all of the physicians and physiologist at the Sport Medicine Centre and the head was Wina Melissa. 

    He proposed that we needed to develop a screening tool as there was none. 
  • This became the focus of my research and my first post-doctoral research worker did a 2-year finish of a study that took us 15 years to complete. 

    This validated the Athlete Sleep Screening Questionnaire. 
  • We've published both stages of the validation in the British Journal of Sport Medicine and now it is the standard screening tool to be used in research. 
  • We also have a clinical programme and we do extensive screening of athletes around the world with the tool. 
  • The tool gave us a foundation to screen athletes, it's valid and reliable and has an output that categorises the sleep problem:

    No sleep problem, mild, moderate or severe. 
  • Based on that, we push back advice to the athlete or the coaches to suggest what they need to do. 

    If they need a doctor I will meet with the athlete online - we can securely do a video conference with athletes though out patient medical system. 

Prevalence of sleep problems in athletes

09:43 - 

  • We're early in the game and thus haven't done large populations, which you need for more confidence in epidemiological research.
  • We also have so many different sports and some have very few elite athletes meaning we have to be careful about what we say. 
  • To date, we're saying that the prevalence of clinically significant sleep disturbance in an elite athlete populations is probably in the range of 10-15%. 
  • The current widespread screening tool is the Pittsburgh Sleep Quality Index which is completely invalid in an athlete population as it's only been validated in medical populations.

    It creates estimates of 50% which is unreasonable. 
  • Athletes are a health population of individuals so using a screening tool designed for psychiatry and medicine does not make sense. 
  • In terms of validity in an age group athlete population, we're at the start of this validation process now. 
  • It's definitely valid in elite athlete populations and is being used in this field. 
  • To start the validation in a general population we screen 1000 runners at the London marathon in 2016 and this is a paper we're about to publish. 

    This will give some data and allow us to start talking about validation in this population. 
  • However, there is no other screening tool, so this is the tool that exists. 
  • We just finished writing a consensus statement for the British Journal of Sports Medicine covering every aspect of sleep and elite athletics and there's only two questionnaires that are really useful in athlete populations. 
  • True validation is a process that requires many years and large populations and we continue this process. 

    I don't think it really effects the validity of using this measure in your training populations for example. 
  • We use it with athletes from 20-70 doing Ironman training as part of our coaching group. 

How to use the tool

15:27 - 

  • We have a link that takes you directly to our website where you can complete the questionnaire for free.

    It will output a letter with your results, which will give you advice: 

    E.g. your score is 7, you're fine and here are the things you need to focus on. 

    Or you're score is 15, you're not fine and you should see your doctor or a sleep specialist. 

Impact of insufficient sleep on athletic performance

16:45 -

  • We've just done a fairly systematic review of this question and the evidence is limited based on poor research methodologies over the last 20 years.

    We're arguing to standardise research method. 
  • In the world of circadian rhythm science we know that if you reduce or disrupt sleep, you affect performance. 
  • Athletes tend to be highly resilient so may tolerate sleep disturbance better than your average individual, but it may still be affecting their ability to perform. 

    We are continuing to develop better strategies to address these questions.
  • we're trying to understand whether wearables really help us or not.

    A wearable is not a sleep screening tool and they cannot detect sleep stages in spite of what they tell you. 
  • Cognitive performance is affected by sleep disturbance and circadian rhythm disturbance (e.g. training out of your sleep phase).
  • Physical performance is very difficult to study but we believe that rate of perceived exertion is affected by undermining sleep as part of recovery. 
  • You need sleep, but it's also important to consider whether it's the right quality sleep and at the right time of day. 
  • In athletes one of the biggest problems is not getting enough sleep largely due to demanding schedules. 
  • A lot of my work with my new post-doctoral researcher is to focus on strategising getting the right amount of sleep through a demanding training or competition schedule. 

Impact of 'one bad night's sleep' on peformance

20:05 -

  • The research would argue that one night of poor sleep can and does affect performance. 
  • However I would argue that if we take proper care of our athletes leading up to a competition, that one poor night of sleep truly isn't going to make a big difference. 

    This is based on my experience working with athletes. 
  • Many athletes have won a gold medal or the National championships on a poor night sleep because it's stressful! 
  • It's not so much clinically and experientially a problem, but the issue is making sure they're not getting a week of poor sleep leading up to that night. 
  • The problem is when you do carefully designed research and sleep restrict individuals you can actually detect negative changes in performance. 

What does good sleep look like

22:11 -

  • The bottom line is in a high volume endurance sport, we would argue that the minimum should be 7 hours of sleep a night. 

    It would be a very rare individual that could get by on 50 hours of sleep a week training at high volume. 
  • We give a window of 7-9 hours ideally. 
  • With teams and athletes we say you need to work out what you need ideally over 7 days. 

    E.g. If you need 8, 7x8 would be 56 so we'd say they need 55-60 hours per week. 
  • If people aren't sure what they need we recommend them completing a sleep log (on paper) - they go away for 28 days, get exactly what they need and log it which becomes their baseline. 
  • We then look at what they're getting - i.e. if they need 8 and they're only getting 6 hours that's a huge gap and gives 14 hours of sleep debt a week. 
  • If the debt is 5-8, this can be made up in a week through strategic napping. 
  • As a coach now you can monitor athletes whose sleep you are worried about. 

    However never monitor if it's not a problem, it's not necessary as you just create problems - especially with sleep as people get anxious about it. 
  • If athletes go to bed, fall sleep within 30 minutes, have one awakening in the night for less than 15 minutes, wake up spontaneously in the morning feeling good then there's no sleep problem. 

Limitations of wearables

25:57 - 

  • We're recently reviewed them all and we have a section of our paper devoted to this. 
  • We don't talk about brands but we talk about research grade versus non-research grade. 
  • The bottom line is that research grade wearable technology has tremendous limitations when it comes to predicting sleep.
  • Most of the devices the public will be using are not research grade devices.
  • We can talk about rest/wake activity with research grade devices but not sleep. 

    They do not predict or capture actual sleep and it's important to know that. 
  • They're less accurate in people who have sleep disturbance - so in the population we really care about they're even less accurate. 
  • Having said that, I'm fascinated by the integration of HRV into activity monitoring and how that might capture recovery - not necessarily sleep. 
  • These devices are now using multiple physiological parameters such as HRV and movement, and they might have promise in the future in predicting stage of recovery, but not necessarily sleep. 

Practical application of wearable devices for monitoring sleep

29:08 - 

  • We look after 3,000 para- and able-bodies Olympic athletes in Canada and our advice to the integrated support teams is to use the Hooper Mackinnon.
  • A person's perception of their sleep is far more important than their objective data. 
  • This correlates well with finding abnormalities on a polysomnogram which is the gold standard in objective measures. 
  • We talk a lot about using paper monitoring or on your phone if that's easier. 
  • The trackers or monitors are used to support the information we're getting from the athlete. 
  • Our coach will often look at the sleep data only once the athlete is reporting difficulties and you can see a drop of in performance. 
  • We can give advice such as backing off on volume if the athlete is only getting 6 hours of sleep a night. 
  • Swimming is a common one where we recommend stopping the morning training for a month and seeing how they come back after that.
  • Those triggers come from performance metrics - are they declining. 

Reasons and remedies for poor sleep

32:36 - 

  • The most common problem we see is insomnia - difficulty falling asleep and staying asleep. 

    It's usually stress related but can sometimes be volume related. 
  • Athletes have two responses to high volume training: excessive sleepiness where they sleep too much, or insomnia from a state of excessive high arousal.
  • It's a normal response to high volume training, if a person develops insomnia in that phase it's sort of normal and they'll trend out of it, usually fine and having achieved the training response. 
  • Insomnia is the most common clinical problem we see and we treat it behaviourally. 

    We have a dense behavioural sleep medicine programme with one clinician who deals with athletes. 

    We do a lot of work with Red Bull with people who video game as they have terrible problems with insomnia. 
  • It's important to know that the most common sleep disorder seen in athletes is in power athletes (e.g. American football, rugby, bob sleigh) where they have sleep apnea because they're large. 

    The prevalence is probably around 5%. 

    It's important to correct because it can seriously undermine training and recovery. 

Screens & caffeine

34:51 - 

  • There's only 24 hours in a day and that can't change, and people need to sleep. 

    Assume you need to sleep 7-8 hours, you've only got the remaining time to train, look after your family, go to work/school. 
  • This becomes an extremely compressed time management issue. If you add on screen time, you blow it out of the water. 
  • Our biggest problem with athletes today is screen time.

    This is why I started working with Red Bull because I wanted to understand the nature of the beast in the most elite athletes (gamers) who are sitting in front of screens 14 hours a day.
  • A lot of our education is about making athletes aware they have to limit screen time severely. 
  • A lot of our athletes travel internationally so technology is how they communicate with their family so we often have to discuss this because it really gets in the way of their rest and recovery. 
  • When it comes to technology there's the light and the impact of that - it's being called into question a little but let's assume it's true that when you expose yourself to this blue light it can dampen down melatonin. 

    We have screen blockers on phones and tablets now and they are quite effective so we always recommend people use these. 

    But more than this it's the interaction with the device - the problem is that people can't remove themselves from the activity of being on the device and that is very counter-productive. 

    It has substantial negative effects on an individual's ability to sleep. 
  • Caffeine and energy drinks would be the next issues. 

    Strategic use of caffeine has en embedded understanding in elite athletes. 

    They understand that caffeine can't be used indiscriminately because it won't enhance performance. 
  • We often have discussions about whether they're using it for performance, fatigue or alertness and what the timing of the consumption is as this will seriously effect their sleep. 
  • With hockey players it's a problem because they consume tremendous amounts of stimulants prior to games and that really affects their ability to sleep after their game. 

    Their sleep times become 2-4 am and then they need to be back on the ice in the morning. 
  • Strategic use of caffeine is okay, limiting dose and being careful about the timing is critical. 

    I think energy drinks have no place in high performance endurance sport. 
  • On a normal training day in the average athlete doing endurance training and have 1-2 sessions a day that are 60-90 minutes each, caffeine prior to training is fine. 

    200-400 mg would be the range if they're using coffee, and that would be it. 
  • You need to keep in mind that caffeine has an 8-hour half life and it suppresses the drive for sleep. 
  • The less you use it the more effective it is and the less impact it will have on sleep. 
  • Combining caffeine with napping is a real strategy with advocate. 

    It can be consumed before or after and the nap should be 30 minutes max. 
  • For the average person I would say don't consume coffee later than noon and if your training is in the evening consume something like an energy bar instead. 

    Often people just need the calories prior to training they don't necessarily need the caffeine. 


40:02 - 

  • Naps should be timed 12 hours from the mid-point of the night time sleep schedule.
  • If you go to bed at 11 pm, wake up at 7 am, 3 am is the mid-point of your sleep schedule. 

    Somewhere around 3 pm (2-4 pm) a 20 minute nap would be recommended if you need 9 hours sleep and you're not getting enough. 
  • Napping is very effective before training. It's a much more physiologically adapted process rather than racing to the gym straight from work. 
  • Training benefit is maximised by reducing states of arousal. 
  • We're not interested in sleep, we're interested in rest. 

    If you can't sleep, just close your eyes take a deep breath and relax for 20-30 minutes every day prior to training in the afternoon. 
  • Caffeine before naps would fit if you're doing it early in the afternoon. 

    Probably before a big training session or one off performance. 


42:21 - 

  • It's important for people to know if they are a lark, a night owl or neutral. 

    Larks like to wake up early, around 5-6 am. 

    Night owls can't fall asleep before 1-2 am and like to sleep in until 9 am. 

    Neutrals are the class 11 pm to 7 am person. 
  • You need to know who you are because if you're a night owl training in the morning research has shown that is not productive and can lead to over-training or under recovery. 
  • Our biggest problem is in night owls, everyone else is relatively fine. 
  • Knowing your chronotype determines how we manage your sleep and training schedule as an athlete.
  • E.g. if there's a swimmer that's a night owl we either correct their sleep phase or we change the training - it's one or the other but you don't keep training them at 6 am when they're not properly awake till 9 am. 
  • Correcting their sleep phase is making them become a lark, and it's done all the time, particularly in the adolescent population. 
  • In adolescent's they have a delay in the sleep cycle and they become night owls, so training schedules should take into account age. 

    At the elite level this group is the ones we're hoping to become podium athletes in their 20's so we want to take care of them. 

    This is one of the reasons I got involved because the swimmers in this age group were dropping off and it was because they were starting in the pool at 6 am. 

Exceptions to the rule 

45:12 - 

  • Often athletes might be sleeping 5-6 hours a night and managing okay and they wonder if they're exceptions to the rule. 
  • Yes there are exceptions but there are very few. 
  • It also depends on age, if that person is 20 years old they have no idea what they need because they have an engine so full of gas they can drive themselves into the ground. 

    In this case it's the coaches job to determine if the athletes perception is off.
  • It's the state of hyper-arousal that people are completely unaware of that's enhanced by technology. 

    People believe that they can perform with very little sleep and that is not true. 

    There will be a fall off the curve at some point. 

Rapid fire questions

48:30 - 

  • What is your favourite book, blog or resource related to sleep or sports? 
  • What is a personal habit that has helped you achieve success?
    • My coach, 100%. 
  • What do you wish you had known or done differently at some point during your career?
    • Listen to my late wife. 

Links, resources and contact

Links and resources mentioned

Connect with Charles Samuels

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  • I get that Dr. Samuels is biased against sleep trackers.
    And I am, of course, biased for them.

    But I agree with his assertions regarding wearables and actigraphy devices.

    However, for me, the use of a sensor in the bed (Emfit, Beddit, Darma, SleepNumber, makes the collecting my hr, rr, hrv, movement and bed occupancy (time in bed) an automated feature that I can track with Training Peaks, and compare my performance against the shorter nights, especially tracking HRV for recovery.

    Still, I agree most athletes won’t really benefit from tracking sleep. Biggest benefit is reinforcing basic sleep hygiene.

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