Sleep and Athletic Performance

Sleep is essential for general health and wellbeing. 

The more we learn, the more we realise that increased sleep duration and quality is associated with better performance in sport and life. The National Sleep Foundation recommends adults get between 7-9 hours of sleep each day for optimal health (1). But it's not clear exactly how much sleep athletes need. It's been suggested athletes require more - closer to 9-10 hours (2). But duration is not the only factor - sleep quality is also important. Getting the right amount of good quality sleep has some incredible benefits for athletic performance. Let's take a deeper look... 

Recovery

Image source: Getty images

Image source: Getty images

For an athlete, sleep is the ultimate form of recovery. It's like a big sponge that soaks up fatigue overnight. This sponge assists with the recovery process so we can adapt from and absorb hard training. The bigger the sponge (sleep duration), the more water (fatigue) it can soak up. 

It's in the deep sleep phases (Stage 3 and 4 NREM) during the first half of the night that we do most of our physical recovery and repair.

The light sleep stages which make up approximately 50% of a total nights sleep (Stage 1 and 2) are also key to both physical and neural recharge overnight. If we don't spend enough time in these phases, we wake up feeling foggy.

Sleep is a WEAPON
— Jason Bourne

Reaction time, coordination and accuracy

It's in Stage 5 (REM) sleep where our brains recovery, learning and development occurs. We create new nerve pathways to consolidate and repair memories, skills and process information. Side note - it's also where we release testosterone (in both men and women). Research suggests that sleep deprivation delays the signals which travel along these pathways, decreasing our coordination and accuracy (2). So much so that inadequate sleep has been likened to being drunk! Williamson and Feyer (2000) demonstrated the longer the duration without sleep (up to 23 hours), performance in cognitive tasks, motor skills, speed and accuracy decreased to levels equivalent to a blood alcohol content of 0.1%. Twice the legal driving limit in Australia!

The duration of REM sleep increases as the night progresses, with the longest duration occurring just before waking. So get to bed early to ensure you get the beneficial effects on mental performance more REM sleep brings.

Injury & illness

Decreased sleep has been associated with an increased risk of injury and illness. Inadequate sleep is immunosuppressive, increasing our risk of upper respiratory tract infections. In a study of 164 adults administered nasal drops containing rhinovirus, those who slept for less than 5hrs were 4.5 times more likely to develop an illness than those that slept for greater than 7hrs (4).

Being sick or injured reduces training availability and is obviously something we want to avoid. The underlying mechanism for increased injury with sleep loss is unclear but is likely due to cognitive impairment and decreased reaction time, along with higher levels of fatigue. All of which can increase an athletes risk of injury.

Mental stamina and mood

Striving to be fitter, faster and stronger doesn’t just require physical effort, it also requires mental stamina. Feeling mentally drained will impact your mood and we all know that missing out on a good nights rest can alter how we think and feel. People who sleep for less than five hours are often sadder, angrier and more stressed (2) which is linked with low motivation and decreased sports performance (5).

Endurance performance

Not a lot is known about sleep deprivation and its effect on short, sharp, anaerobic power type exercise, but a number of studies have shown decreased endurance performance (6, 7, 8, 9).  Sleep loss clearly resulted in increasing 3km time trial duration in cyclists (7), decreased time to exhaustion in volleyball players (6) and decreased treadmill run distance covered in a 30 minutes self-paced test (9). This appears to be due to an increase in our perception of effort (how hard you feel you're working) (8). It may also be due to an alteration in substrate availability as pre-exercise muscle glycogen (our carbohydrate fuel tank) has been found to be decreased after sleep deprivation (10). 

Improve sleep efficiency

Multiple studies show the significant implications sleep deprivation has on performance. From impaired accuracy, coordination and reaction time, fatigue, inadequate recovery, to increased risk of injury and illness. So what can we do to improve our sleep efficiency - both duration and quality?

  • Get to bed earlier, aiming to get 7-9 hours of sleep every night.
  • Stop using your phone in bed. The blue light it emits affects our normal sleep hormone production (melatonin)
  • Ensure all of your devises are set up with night mode so they switch to a more warm, orange hue after sunset.
  • Make your sleep environment comfortable, dark, cool and quiet
  • Establish a regular sleep routine
  • Eat foods that assist with promoting sleep - more on this next time!

Next up - we take a look at food to boost sleep performance. Stay tuned!

 

References

 1. Hirshkowitz et al., (2015). National Sleep Foundation's updated sleep duration recommendations: final report. Sleep Health: The Journal of the National Sleep Foundation. 1(4), 233-243

2. Bird, S, P. (2013). Sleep, recovery, and athletic performance: a brief review and recommendations. Journal of Strength and Conditioning. 35:43-47.

3. Williamson, A., Feyer, A. (2001). Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication. Occupational and Environmental Medicine, 57: 649-655.

4. Prather, A., Janicki-Deverts, D., Hall, M. and Cohen, S. (2015). Behaviuorally assessed sleep and susceptibility to the common cold. Sleep. 38: 1353-1359.

5. Totterdell, P., Reynolds, S., Parkinson, B., & Briner, R. (1994). Associations of Sleep with Everyday Mood, Minor Symptoms and Social Interaction Experience. Sleep, 17(5), 466-475.

6. Azboy, O, Kaygisiz Z. (2009). Effects of sleep deprivation on cardiorespiratory functions of the runners and volleyball players during rest and exercise. Acta Physiologica Hungarica. 96, 29-36.

7. Chase et al. (2017). One night of sleep restriction following heavy exercise impairs 3-km cycling time-trial performance in the morning. Applied physiology, nutrition, and metabolism. 1-7

8. Fullagar, H, H, Skorski S, Duffield R, et al. (2015). Sleep and athletic performance: the effects of sleep loss on exercise performance, and physiological and cognitive responses to exercise. Sports Med. 45, 161-86.

9. Oliver, S, Costa, R, Laing, S, et al. (2009). One night of sleep deprivation decreases treadmill endurance performance. European Journal of Applied Physiology. 107, 155-61.

10. Skein, M, Duffield, R, Edge, J., et al. (2011). Intermittent-sprint performance and muscle glycogen after 30 h of sleep deprivation. Medicine and Science in Sports & Exercise; 43: 1301-11.

11. Watson, A. (2017). Sleep and Athletic Performance. Current Sports Medicine Reports, 16(6), 413-418.

The Different Stages of Sleep

Many of us think of sleep as a time when the mind and body shut down, but in fact what happens when our head hits the pillow is quite the opposite. Sleep is a dynamic process – our brain changes its state many times as we pass through the five stages of sleep in approximately 90-minute cycles. The first four stages of sleep make up our non-rapid eye movement (NREM) sleep and the fifth stage is when rapid eye-movement (REM) sleep occurs.

Across NREM sleep we move from very light sleep during Stage 1 to very deep sleep in Stage 4. It’s very difficult to wake a person who is in Stage 4 sleep. Typically, our eyes do not move during NREM and we have low muscle activity, although all of our muscles are still able to function.

                Stage 1 – Very Light sleep: We drift in and out of sleep and can be awakened easily.

                Stage 2 – Light sleep: Where eye movement ceases.

                Stage 3 & 4 – Deep sleep: We’re difficult to wake and have no eye movement or muscle activity.

                Stage 5 – REM sleep

During Stage 5 or REM sleep our brain waves are as active as when we are awake and breathing becomes more rapid. The limb muscles are temporarily paralysed, our body does not move, eyes can dart rapidly in all directions and we dream vividly.

A typical night under the covers isn’t simply four to six of these 90-minute sleep cycles pieced together. In the first two to three cycles of shut-eye we spend most of our time in deep Stage 3 and Stage 4 (NREM) sleep. During the final two to three cycles we enter more REM sleep which is accompanied by some lighter NREM sleep. 

Cycling through the sleep stages is important for preventing tiredness and irritability the next day and maximising the benefits of sleep. Next up, we’re taking a look at how sleep can boost performance. Stay tuned!

Noosa Race Recap

It was the night before my first ever Olympic Distance Triathlon. After 10 months of preparation, I was ready, albeit incredibly nervous. Sitting down to a home-cooked dinner with my support crew, I felt like the biggest kid eating my large bowl of pasta, side of garlic bread, all washed down with pasito (dietitians orders). As I forced it down (nerves!) I looked enviously at my friends casually enjoying their pizza and wine without a care in the world. All I wanted to do was grab the Shiraz and neck it myself! I called it an early night and before I knew it, the alarm was going off. With a blink it was race day. Ahhhh!!!

My first thought that morning was, “I can’t wait to wake up tomorrow and not feel so nervous”. I knew I was prepared and I knew I would finish, but that didn’t stop the pre-race butterflies. I got myself ready, feeling like livestock being marked up; right arm tattoo, left calf tattoo, left ankle tag… It was soon time to leave for the final transition set up.

I couldn’t have asked for a better race day. Noosa definitely turned on the weather and whilst it was hot, the conditions were in my favour. Time flew that morning and before I knew it, I was standing nervously on the beach waiting for my wave to start, surrounded by my friends and family doing their best to distract me.

The swim, my weakest and biggest concern, unexpectedly turned out to be my favourite. The water was beautiful and clear. We were off and I found my own space, settling in quickly. I kept on course (mostly), made a bee-line for the beach and was stoked to finish in 30 minutes without drowning.

Quick transition (well, as quick as I could without doing a flying mount) and I was onto the bike course. I felt fatigue in my quads straight away so perhaps my taper wasn’t enough in the week leading up. Still, I was determined to maintain an average speed ~ 30km/hr and used everything I could to push through the burn, conscious to save a little for the run. Descending Garmin hill was my highlight and I even cracked a new PB top speed on the bike; it was so much fun! Coming off the bike, I checked to see I had done enough to hit my goal time of 1hr 20. Right on target.

I did some quick maths and realised that sub-3 hours was within reach. Yass! Running is my strength but it was hot (~27°C), my feet were burning, and my body was tired. Learning the hard way in previous run races, I knew I had to pace sensibly…These lessons paid off as it soon became apparent the run was going to be far more challenging than I’d thought. I needed every ounce of energy to make it to the finish line. A friend had given me some valuable advice the day before and this mantra repeated in my head; “Pain is temporary. Glory lasts forever”. I kept to a consistent pace and somehow even managed a sprint finish.

I went into race day hoping to finish around 3 hours. As I crossed the finish line, I sneaked a peep at my watch to see the time 2:55! I couldn’t believe it! I was ecstatic! Thank you Noosa,!

Whilst I exceeded my expectations at Noosa, there is always room for improvement.

Some of the key things I learnt from race day…

  • Go over the entire swim course (not just the first half) in your head before the start
  • Revisit taper week to ensure I’m feeling fresh and ready come race day
  • Stick more to the left on the bike course around tight turns. There were a couple of close calls…
  • Tighten up transitions and learn how to flying mount

I’ve definitely caught the triathlon bug and after having the time of my life on Sunday, all that’s left to decide now is …which race to do next!?

Erin Lawlor

Dietary Periodisation: What is it but how do you do it?..

We talk about periodising nutrition all the time, but WHAT the heck is it? And HOW do you do it?

Nutrition Periodisation is the use of planned nutritional strategies aimed at maximising the results from specific training sessions to improve performance (1). It is just like having a training plan but for your nutrition, where your nutrition is planned around your training to get the most bang for your buck out of it.

Periodising nutrition primarily manipulates our glycogen stores, or our carbohydrate fuel tank.

There are a few ways dietary periodisation can be used:

1. Train low

This is where you train with low glycogen stores. For example, you train first thing in the morning on an empty stomach or you don’t quite top your glycogen stores back up between sessions. This allows your body to learn to run more efficiently on a lower fuel tank. For athletes that train twice or even three to four times a day, chances are they are probably running on lower glycogen stores for some of those sessions.

2. Sleep low

This is where you sleep with low glycogen stores. For example, you have a hard, glycogen depleting session in the evening and don’t include adequate carbohydrate with dinner to fully refuel your glycogen fuel tank overnight. You’re going to sleep ‘low’. This allows the body to adapt overnight. It’s then important to fuel up before your session in the morning (especially for females) as this has implications on iron and calcium pathways.

3. Recover low

This is where you delay refuelling in that immediate post-exercise recovery window. Not refuelling immediately after training allows us to adapt to changes occurring as a result of training (2).

4. Train high

This is where you train on a full glycogen tank. This not only supports a quality training session, it also trains your gut to absorb carbohydrate efficiently and can maximise the amount of carbohydrate we can use for energy each hour (1).

By manipulating our carbohydrate availability around sessions, we can maximise our training response. Training with high carbohydrate availability, improves performance, especially for the high intensity sessions where top end speed is required (1). By training with low glycogen stores, we force our body to adapt, to utilise fat as a fuel, making this pathway more efficient and improving aerobic performance. However, when we are running on an empty carbohydrate tank, the quality of our training is compromised.

We train to get fitter, faster and more efficient. We spend hours and hours training, but if we haven’t got our nutrition sorted, it can be harder to reach our goals. Invest in some planning of your nutrition, periodised across your training week to get the most bang for your buck. Improved performance was observed after just 1 week of periodised nutrition in cyclists (3).

As Accredited Sports Dietitians, periodisation is our forte! We can help you work out which method to utilise when across your training week as you can’t do them all at once. Nutrition periodisation is most effective when following a plan and choosing the most appropriate training sessions to pair it with based on your goals (2).


Now let’s talk about HOW to periodise your nutrition... 

Here is an example of the same recipe, but adjusted for carbohydrate content depending on the goals of that meal.

Image 1 is our chicken burger patty with an Asian slaw and soy dressing.

Image 2 is our chicken burger patty on a wholegrain wrap with salad

Image 3 is our chicken burger patty on a large Turkish bread roll with salad

You’ll see that the protein portion of each meal remains the same. And the SIZE of the meal is also similar. Yet the carbohydrate content ranges from 20g up to 90g. This my friends, is an example of HOW you periodise your nutrition. You're welcome.

Now we don't want to give all of our secrets away so the detail stops there, sorry :)

Dietary Periodisation

References: 

1. Jeukendrup, A, E. Periodized Nutrition for Athletes. Sports Med. 2017; 47 (Suppl 1): S51-63.

2. Marquet L, A et al. Enhanced Endurance Performance by Periodization of Carbohydrate Intake: “Sleep Low” Strategy. Medicine & Science in Sports & Exercise. 2016; Vol 48(4): 663-672.

3. Marquet 2 et al. Periodization of Carbohydrate Intake: Short-Term Effect on Performance. Nutrients. 2016; 8(12): 755.

Sports Supplements

Words by Accredited Sports Dietitian, Taryn Richardson, Dietitian Approved

Sports Supplements are everywhere!  I struggle to keep up with the latest products on the market with new brands popping up every week. As many athletes search for that ‘magic bullet’, sports supplements have become a multi-billion dollar industry. In fact, a recent study found that 40-70% of athletes take supplements.

A nutrition supplement, as the name suggests, is designed to supplement the diet and should never replace it. My approach as a dietitian is always “food-first” as your day-to-day nutrition is where you will see the greatest health and performance benefits long term. Supplements are considered the sprinkles, on the icing on the cake. It’s important to get the foundations of a balanced, healthy diet in training right first (the sponge), before adding the icing and even considering the sprinkles.

Supplements typically fall into three main categories: Sports foods and fluids, Medical supplements and Performance supplements.

Sports foods and fluids

These include an extensive list of sports drinks, gels, chomps, bloks, bars, protein powders and recovery drinks. They are easily accessible, portable, convenient and provide concentrated nutrients when real food may not be practical.  In most situations though, real foods can take the place of sports foods if you’re organised. Sports foods and fluids can be expensive, may be completely unnecessary, are energy dense and can cause gastrointestinal upset in some people.

Medical supplements

Are used to treat a known deficiency such as Iron or Vitamin D for a short period of time. They can be pills, potions or powders and should only be taken when recommended by a doctor, accredited sports dietitian or other health professional after a blood test and/or diet review. Taking un-prescribed medical supplements can be dangerous and have harmful long-term effects. 

Performance supplements

Approved ergogenic aids or performance-enhancing supplements have been proven in scientific trials to provide a performance benefit, when used according to a specific protocol in a specific situation in sport. Things like caffeine, creatine and bicarb form part of this list. However there are many other popular supplements on the market promising remarkable super-human powers that don’t deliver. In some cases, these supplements may actually impair health or performance.

Stay safe

A recent study found that 80% of certain supplements didn’t contain what the label said (scary). The risk of contamination with banned substances is real and should be at the forefront of every athletes mind. Especially now that age group drug testing is a common occurrence. The supplement industry is largely unregulated, and traces of banned substances can find themselves in products by accident. You can take responsibility by checking your product on the ASADA website. You can also look for products that have been through a contamination screening process such as Informed Sport or Hasta in Australia. 

Be smart

Be an informed supplement user. Before purchasing anything, do you research and talk to a professional. Ask yourself three questions – Is it safe? Is it legal? Does it really work? If it sounds too good to be true, chances are, it probably is. Everyone has an opinion but be mindful that what works for one, may not work for another. An Accredited Sports Dietitian can help you work out what supplements are best for you and your sport.

Source: projetopedalando.com.br

Happy Training

Taryn

Dietitian Approved