Female Athlete Hydration and Fueling - Review of the Book ROAR

I have been reading the book ROAR by Dr. Stacy Sims. It is amazing read and geared specifically to women. I am on my second time through. There is just so much good information, and how the book is structured takes some time to understand. The book was recommended in a course I took that highlighted some new thoughts on hydration and nutrition. To be honest, it took a bit to get my head around the difference between absorption and fueling. It is a concept that most nutritionists do not differentiate between (at least to my knowledge). Sims drives home the saying, “food in your pocket and hydration in your bottle.” Sims does an amazing jog of explaining how the female body works. She dives deep into how hormones impact the female athlete during the menstrual cycle, pre-and post menopause and pregnancy. She provides prescriptive guidelines on hydration and fueling to help the female athlete throughout the different stages of her hormonal journey. I do not provide information on fueling and hydration in this article as it is very in depth. I encourage you to read the book.

As a former elite female athlete, I understand the struggles that female athletes are challenged with when it comes to hormones and performance. When I competed, the literature and research available specific to the female was limited. Much like Sims, I was frustrated with coaches suggesting to get on the pill to control my menstrual cycle. It did not make sense to me given how the pill can elevate estrogen and progesterone.

As a coach, I have finally found a resource that can help me better coach my female athletes in areas of hydration and fueling for training and racing. The concepts of fueling and hydration that Sims provide are not foreign. What Sims does extremely well is connecting the dots between the female hormonal cycle and what has to change in hydration and fueling during training and racing.

My goal for this article is to summarize some of the key points from the book. Every female athlete and coach of females should read this book. I don’t recall much of my high school biology class (except that my teacher sat at the back of the class and picked his nose) but Sims refreshes this for us.

Human Biology Refresher

• The largest muscle fibers in a female body are endurance fibers (Type 1).
• Essential body fat for females is 12 percent and for 4 percent for males.
• Females pump out 30 percent less oxygenated blood than males.
• Males have 6 percent more red blood cells and 10 to 15 percent more hemoglobin (molecule that carries oxygen in red blood cells).
• Female VO2 is 15 to 25 percent lower than men.
• It takes longer for females to sweat and this impacts heat tolerance.
• Females rely more on fat whereas males rely more on carbs. This is important to understand when it comes to the menstrual cycle and pre-and post menopause. Understanding the shifts in estrogen and progesterone levels and how to manage this is the main theme in the book.
• Females are more likely to sweat out excess sodium and eat into their muscles for energy.
• The metabolism of a female drops back to normal within three hours post exercise compared 21 hours for a male.

Key Concepts From the Book

• Performance levels are highest once your period starts and days five to 11 following your period (Follicular phase). Estrogen levels surge on day 12.
• Five days before menstruation, estrogen and progesterone reach peak levels (Luteal phase). Why is this important to know? Estrogen reduces carbohydrate burning ability so when estrogen surges it will have an impact on high intensity performance. Female athletes will feel unfit and unable to push hard. High levels of progesterone promotes catabolism. It increases the breakdown of muscle tissue and makes it more difficult to access amino acids. Key message here is that one-third of muscle tissue is composed of the amino acids leucine, isoleucine and valine. Leucine triggers muscle repair and growth.
• Estrogen and progesterone are elevated during the luteal phase (days 14 to 28 of the cycle), and peak five days before menstruation. During this time blood plasma can drop up to 8 percent. This can impact hydration and cooling during exercise. Plasma volume is the amount of fluid in our blood. When it is low our blood is thicker, less blood is pumped out, and exercise will feel harder. Progesterone elevates core temperature, and this means higher loss of sodium.
• From ages 35 to 50 estrogen declines by 35 to 50 percent and progesterone by 75 percent. In addition, there is relatively higher estrogen levels compared to progesterone.
• Wake up call – postmenopausal females have a hard time metabolizing fructose in processed foods (for example, gels). Further, synthesis of protein changes and there is a higher rate of protein breakdown. Also, sweat rate is lower, and the ability to feel thirst declines. There is also a decreased insulin sensitivity. Insulin instructs the body what to do with blood glucose. Insulin communicates to our cells to take up blood glucose to use as fuel or store as glycogen. Decreased insulin sensitivity results in higher amounts of glucose left in circulation and eventually stored as fat.

Read the book

This book is a handbook for female athletes and coaches of female athletes. The book teaches you about the female body and provides exact details on hydration and fueling during exercise and through the different stages of the female hormonal phases.

My Own Advice

To maintain and improve bone density and lean muscle, heavy resistance training is needed. I felt that even though the book does go into exercises and some strength training, it does not stress the need for heavy resistance training. My suggestion around types of exercises are centered around things we need to be able to do in our everyday life. We need to be able to lift, carry, pull and push. In addition, everything we do requires grip strength. Throw away the biceps curls and start working on functional exercises which focus on the anterior and posterior chain. I also suggest adding exercises that help with balance, and this should be part of every routine regardless of age.

• Deadlifts
• Farmer’s Carries
• Sled push and pull
• Standing or walking with a sandbag on your shoulders
• Squats with weight
• Walking Lunges with weight
• Push ups
• Pull ups and body holds

Training systems

Understanding the relationship between the intensity of a training session and its optimal duration is poorly understood. Endurance athletes derive energy from three different energy systems. This means that an endurance athlete needs to train all three.

Muscles are fuelled by different energy systems. The systems are:
- The creatine phosphate system
- The lactate system
- The aerobic system

When we train we want to target these energy systems in a way that reflects the demand of the the event we are training for.

Simplified, the three training zones are:
- Zone 1- aerobic, easy, recovery, long slow distance. I can keep going and going. Heart rate is under 80% but better around 70-75% of maximum. Energy system used is aerobic system.
- Zone 2 - Threshold training. Moderately hard. Heart rate is 80-85% of maximum. Energy system is aerobic system with use from the lactate system. 
- Zone 3 - Very high intensity, race pace. Training is very hard. Heart rate is over 85% of maximum. Energy system used is lactate with use from the creatine phosphate system.

Knowing when and how to train these systems based on the event we are training for is when improvement in performance is made. In addition, it is important to understand how much time is spent training in these zones based on the distance of event we are training for.

Tips on choosing a coach

Looking for a running coach? Here are some tips:

1. Certifications. Look for a coach who has National Coaching Certifications from National Governing bodies at greater than the first level. 

2. Experience both in length and breadth. A coach who has been coaching for several years will have been exposed to lots of different athletes and will have learned what is needed for different levels of athletes with varying training years. In addition, a coach who coaches track, cross country, road and trail in all distances brings a lot to the table.

3. INTERVIEW COACHES and ask:
How they structure training? How often can you contact them? How would they approach helping you reach your goals? Do they plan your race schedule or does the athlete have the reigns on this?

4. Ask to meet current athletes. I always encourage new folks to come out for a couple of practices, if they are local to my area.

5. Ask for the names of a couple of athletes they have coached in the past, and also a couple from who they currently coach. Make connection with these athletes and ask for their view on the coach.

6. Look for results. A coach who has a reputation for improving performance of athletes is only part of an equation. The other part of the equation is the length of time athletes have been with a coach. A good coach has the ability to keep athletes accountable and responsible. In other words, they ensure that the athlete understands that training is a process of learning and adapting. It is not the same thing over and over again. A good coach knows when and how to move the training process along so that the athlete makes strides every year.

7. Make sure that the price that a coach charges is justifiable. The experience level must match the price being asked. Look for someone who is a professional and not a hobbyist. There are a lot of online coaches with pretty websites; however, that does not mean that they have adequate experience coaching. Do your homework by going through #1 to #6.

8. Experience as an athlete adds to the toolbox a coach has but it is not experience as a coach. A good coach was mentored by other coaches. Ask the person who their mentors were. I had some amazing mentors both as an athlete and a coach. I owe a lot to those people.

Weighing in with Whey Protein

Lately, I have been asked questions around post exercise recovery nutrition and nutrition for getting lean and for weight maintenance.  I am going to discuss whey protein and its benefits. 

What is Whey Protein

Most of us grew up on drinking milk.  Milk is comprised of two types of proteins - 80% casein and 20% whey proteins.  Whey is the liquid by-product of milk that separates during the manufacturing process.  Following pasteurisation, the whey clumps and is extracted. 

Whey protein can be way too confusing.  If you walked into a sport supplement store you would notice that, there are many whey protein products.  Here is a summary that provides the highlights:

1.       Whey protein concentrate consists of around 80% protein.  It contains naturally occurring carbohydrates and fats.  This make it a calorie dense supplement (i.e. contains high levels of calories per serving).  It contains some lactose.

2.       Whey protein isolate consists of 85% to 95% protein.  This type of whey has undergone further purification to minimize the macronutrients (see side bar) and enhance the protein content.  As such, it has less lactose and fat.  This process removes micronutrients (see side bar) and subfractions (see side bar) that aid in boosting our immune system. 

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Side bar for those of you who missed out nutrition courses in high school and hated math and biology:

There are three macronutrients required by humans: carbohydrates (sugar), lipids (fats), and proteins.  Each of these macronutrients provides energy in the form of calories. For example:

• In carbohydrates, there are 4 calories per gram
• In proteins, there are 4 calories per gram
• In lipids, there are 9 calories per gram

Micronutrients are vitamins and minerals.

Subfractions are smaller amino acids and peptides.

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3.       Whey protein hydrolysate can be a concentrate or an isolate in which some of chemical bonds in the whey have been broken after being exposed to heat, acids or enzymes.  This process allows for the whey to be absorbed more rapidly in the stomach compared to the other whey proteins.  It causes a 28 to 43% greater spike in insulin levels than isolate.

Benefits of Whey Protein

There are numerous studies which have found that whey protein maximizes lean body mass and fat free mass gain.   It also has been proven to improve upper and lower body strength.  Here are the benefits of whey protein:

• As a recovery drink, it is rapidly digested and absorbed. 
• It contains the amino acid leucine which is responsible for muscle building.
• It aids in body fat reduction or weight management while at the same time conserves or increases muscle mass.  Power to weight ratio improvements are the result.

What is the right amount of Whey Protein?

• 20g of whey protein is the magic number.
• For high volumes of training 20g of whey protein and 40g to 60g of carbohydrates.  This helps recovery by replenishing muscle glycogen.

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BIG and IMPORTANT Side bar

Glycolysis is the breakdown of carbohydrates. It lasts from roughly ten seconds into physical activity up to about two to three minutes. The energy for glycolysis comes from glucose, or our stored form of glucose called glycogen.  Glycogen is stored in muscle tissue and the liver.  The average person holds about 1,500-2,000 calories of stored glycogen.  The liver contains about 100g of stored glycogen and muscle tissue contains about 400g of stored glycogen.

The liver is responsible for controlling blood sugar between meals. Our muscles main responsibility is to move bones.  This allows us to do all the locomotive tasks associated with daily living.

Glycolysis is an anaerobic metabolic pathway.  Carbohydrates are the only macronutrient that can be synthesized into usable ATP under anaerobic conditions.  We need to make sure we take in enough carbohydrates to fuel glycolysis during activity and to keep our glycogen stores full.  A reduction in muscle glycogen is associated with fatigue.

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What is my recovery routine?

I personally use a combination of:

• Whey Protein Islolate (I use ON Gold Standard).  A serving size provides 24g protein, 3g of carbohydrates 1g of fat and 120 calories.
• Skratch Recovery Mix.  A serving size provides 36g carbohydrates, 7g protein, 3.5g of fat and 200 calories.

Within 90 minutes of this, I consume a meal or snack which is also a combination of carbohydrates and protein.  If for some reason a meal is not possible within the 90 minutes, I consume another of the same mixture described.

If I am trying to reduce my weight or get lean, I will use a hydrolysed whey protein with less carbohydrates.  I will shoot for 20g protein and 20g carbohydrates.

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Micellar Casein Protein and Recovery

This article was about whey protein, but don't discount the value of micellar casein protein.  The video does an amazing job of describing muscle protein synthesis (MPS) and muscle protein breakdown (MPB).  For athletes, pre-sleep protein is essential.  Ingesting micellar casein protein one to two hours before sleep is beneficial for recovery.  The dosage recommended is 50g.  Watch the video.

I have read a lot of different articles on casein, and to be honest, as a supplement there are several differing opinions.  Grade and processing is a big factor.  I think I will stick to whole casein as found in raw milk, milk protein concentrate and aged cheese.  

Picking up your heels in running

Learning to pick up your heels in running is one of the hardest things to master in running form. When running, the heel should be pulled up directly under you and not behind you. If the foot comes up behind you, it means that you are running with a hip flexor dominant swing phase. Injuries to the psoas, IT band and rectus femoris are likely to occur. It is also likely that the pelvis is not level when running.

Learning to pick your foot up and pull it underneath your hip requires engagement of the hamstrings during the early to mid swing phase. This offloads the work of the hip flexors to pull the swing leg through under the body.

Practicing this allows there to be more balance around the hip and pelvis. Further, getting those hamstrings activated during the swing phase helps avoid the tendency to sit back when running (I call this sitting on the toilet running).

Here is a drill that will help keep the pull movement under the body rather than becoming more of a flick behind you.

Heavy Load Resistance Training for Endurance Athletes

Endurance athletes have commonly followed the approach of endurance based resistance training.  This involves performing high repetitions and sets in resistance training.  However, in recent years this view has changed.  Heavy load resistance training (HLRT) has become more of the norm.  HLRT involves using low repetition numbers with a moderate set numbers.  Loads are usually more than 80% of your one repetition maximum.

I decided to look at this logically and attempt to explain it in more simple terms.  Let’s start by looking at the muscle fiber types and their characteristics to help explain why HLRT is beneficial to endurance athletes.

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Characteristics of Muscle Fiber Types:

Type I Slow Twitch (ST) – slow contraction time, small motor neuron, high resistance to fatigue, low force production, high mitochondrial density, high capillary density, high oxidative density.  Used in aerobic activities.

Type II A Fat Twitch (FT-A) – fast contraction time, large motor neuron, intermediate resistance to fatigue, high force production, high mitochondrial density, intermediate capillary density, high oxidative density.  Used in long term anaerobic.

Type II B Fat Twitch (FT-B) – very fast contraction time, very large motor neuron, low resistance to fatigue, very high force production, low mitochondrial density, low capillary density, low oxidative density.  Used in short term anaerobic.

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Muscle fiber composition in the body is genetically determined.  However, numerous studies have proven that both the structure and metabolic capacity of individual muscle fibers can adapt to different types of training.

When we look at muscle recruitment in exercise, slow twitch muscles are recruited first.  This is regardless of the intensity.  As intensity level increases, recruitment of fibers is slow twitch first, then fast twitch A and lastly fast twitch B.  When we apply different types of training methods we are effectively trying to recruit certain muscle fibers types or to get certain muscle fiber types to take on characteristics of other muscle fibers types. 

For example, we could train FT-B fibers to take on some of the endurance characteristics of FT-A fibers.  This is how HLRT comes into play.  HLRT results in the body being able to recruit FT-B fibers as if they are FT-A fibers.  We are trying to make the muscle fiber stronger, more resistant to fatigue, and have greater mitochondrial and oxidative density.  Totally logical.

Of course, there are other benefits to HLRT.  HLRT, like plyometric training, increases leg stiffness which improves performance economy.  HLRT also stimulates neuromuscular efficiency and builds more power. 

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Summary

A muscle which is stronger is going to be more resilient and fatigue resistant, and have better overall performance economy.  In endurance sports, performance economy is key.  If an athlete can use less effort at faster speeds, they undoubtedly become a faster athlete.  Totally makes sense to me.

The type of exercises that I recommend for endurance based athletes includes dead lifts, squats (different variations), steps ups, and lunges.  Like a properly mapped out endurance plan, a strength program needs to follow a periodization structure to reap the biggest benefits.

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Run Training and Types of Training Explained

Training for running is not complex.  It is pretty straight forward but it always surprises me when people train for years and cannot figure out why they do not improve, have chronic fatigue, or are constantly injured.

The goals of a structured training program can be summarized into six points.  Jack Daniels describes the goals as:

1.       To improve the body’s ability to transport blood and oxygen.

2.       To increase the ability of muscles involved in running to use the available oxygen and convert carbohydrate and fat fuel into useful energy.

3.       To increase lactate threshold to enable faster running speed.

4.       To increase aerobic capacity by increasing VO2max.

5.       To improve speed.

6.       To decrease energy demand by improving running economy.

I start with these goals as I believe that the linkage between these goals and the type of training to enable these goals is not clearly understood or it is simply ignored.  If one is going to spend time doing an activity, I think they should learn to train properly to maximize benefits.  I admit, I get extremely frustrated when people tell me how hard they run or how much they run.  So what.  If one is not training properly that means absolutely nothing.   If you win races and run exactly the same time every time, then you should start to question your training.

The second thing that frustrates me, is that I see people training together doing exactly the same workout without considering level of the runner or the volume of running per week.  Someone who runs 40 km a week should not be doing the same volume of intervals as someone who runs 100 km a week.  Nor should someone who is relatively new to running be doing the same type of intervals as someone experienced.

I may have two athletes do a workout that on paper looks exactly the same but the purpose of the workout is different.  For example, 5x1000 meters.  One athlete may be doing this at threshold and the other at VO2max.  The recoveries may also be the same or different as they are at different levels.

So let’s get back to the basics.

Easy and Long Runs

Purpose: To improve cell adaptation, promote glycogen depletion, to teach the body to use fat as fuel. 

How:  Run 65% to 70% of VO2max. 20 minutes to 2 hour 30 minutes.

Example:  45 minute easy run the next day after a hard workout.

Threshold Runs

Purpose: To build strength and speed.  By running at or very near your lactate threshold, your body will become more efficient at clearing lactic acid and reusing it to fuel your muscles.  Threshold runs simply teach us to endure greater intensity for longer periods of time.  For an endurance athlete, this is key.

How: Run 86% to 88% of VO2max.  Tempo runs, Tempo intervals, Cruise Intervals.  It is a pace that you could maintain for an hour in a race.

Example 1: 20 min tempo run.

Example 2: 8 x 1000 meters with 30 second rest interval.

Example 3: 2x10 minutes with 1 to 2 minutes’ rest interval.

Intervals

Purpose: To increase your maximal aerobic capacity (VO2 max).

How: Run 98% to 100% of VO2max.  It is a pace that you could maintain for 10 to 15 minutes in a race.  It is often quoted as 3 km race pace.  Running these too fast results in training the wrong system and defeats the purpose which is to improve your aerobic capacity.

Example: 30 second to 5 minute intervals.  I stress time here as opposed to distance as I differ the workout distance based on level of runner.  For example, a slower runner covers less distance in 5 minutes than does a faster runner.  The rest interval varies but it should be equal to or less than the interval time.  As athletes become stronger, I tend to shorten the rest interval.

Speed

Purpose:  To improve mechanics. 

How: Greater than VO2max.  Intervals of less than 2 minutes.  Again, using time as opposed to distance as we need to account for a runner’s ability.  The rest interval would be up to four times it took to do the interval.  For example, 30 second interval would get a rest interval of 2 minutes.

Marathon Pace workouts for Marathon Runners

Purpose: To enable an athlete to spend some time running the pace at which they hope to complete the marathon in.

How: Run up to 25 km at marathon pace.  I incorporate a build up to 25 km over time in a marathon program.  I also encourage athletes to run a half marathon race at marathon pace or slightly faster.  I usually start runners at 10 to 12 km and gradually build them to 25 km over a 16 week to 20 week period.  I like to schedule a marathon pace run every three to four weeks.

Keeping your female menstrual cycle healthy while training hard

Written by Meaghan McCollum.

Meaghan is a naturopathic doctor practicing in Bridgeland, Calgary. She helps people achieve hormonal balance naturally in all stages of life and activity levels. As a avid runner herself she thoroughly enjoys working with endurance athletes. She owns a integrative naturopathic clinic and retail store called Naturmend. Check her out at: https://www.naturmend.com/

Endurance exercise has long been known to disrupt the natural female hormonal cycle. Around 1/4 of all female runners experience frank menstrual cycle disorders (1). And as many as 78% of regularly menstruating female runners (elite and recreational) experience disruptions to ovulation in at least 1 out of 3 cycles. (1). That’s a lot of us.

What exactly are disruptions to the menstrual cycle? Any of the following can occur with greater frequency in athletes:

•       Luteal phase deficiency (disrupted / shortened 2nd half of menstrual cycle)

•       Anovulation (not ovulating leading to infertility)

•       Oligomenorrhea (getting periods less frequently such as every 40-90 days)

•       Amenorrhea (not getting a period at all)

•       Menorrhagia (Excessive bleeding)

•       PMS (no need to explain this one) & PMDD (extreme PMS)

These can be inconvenient, unpleasant symptoms yet also point to disruptions in the healthy balance of hormones. These imbalances can have long term health implications, and in the immediate future can also lead to decreased athletic performance (2,3). All good reasons to pay attention to these signs and work to achieve a better balance.

Fat is important for hormonal balance. We now understand fat tissue to be an important hormone contributor in the body. Two hormones called leptin and adiponectin are produced and released by fat tissue. When there is a rapid decrease in body weight and fat, leptin drops and adiponectin increases. The result of these shifts can affect female hormone release and prevent ovulation (4,5). Both of these effects are instigated by rapid weight loss, emphasizing the importance of gradual weight loss in athletes and maintaining appropriate body weight.

Some women once they drop below a certain body fat percentage may experience disruptions in their cycle even if the weight loss was gradual. Although dropping below a certain body fat percentage was a popular theory in menstrual disturbances in athletes, it is not true for every woman and is very dependent on individual requirements for body fat.

Stress and cortisol

Cortisol is a stress hormone that is released during exercise particularly longer duration and higher intensity exercise. Cortisol can also impact the female menstrual cycle by suppressing upstream hormone release from the brain (6). Managing cortisol levels during training and non-training times could reduce the overall load of cortisol on the hormonal system. This is also pertinent to emotional stress which results in greater cortisol levels as well.

Progesterone and estrogen are essential for your monthly rhythm

Progesterone and estrogen are hormones important in the normal functioning of the female menstrual cycle. Both are affected by intensive and prolonged exercise and are typically suppressed with chronic exercise (7). This of course has implications on the proper functioning of the menstrual cycle. Additionally estrogen plays an important role in preventing excessive muscle damage following endurance exercise (estrogen study)

What can you do to keep your female hormones cycling regularly and healthfully?

•       When trying to achieve a lower weight, take a slow and steady weight loss approach. This is to prevent the hormones leptin from dropping and adiponectin from increasing, which are connected to the proper function of your menstrual cycle. Eat enough food to power your training.

•       Increase exercise intensity in a slow and steady approach (a.k.a: listening to your coach).

•       When under significant emotional stress consider cutting back on intensity and/or volume of training. This will not only function to keep your cycle on track, but also help to prevent injury.

•       Practice good nutrition pre, during and post workouts. This helps to keep cortisol release to a minimum by regulating blood sugar.

•       Balance the stress of intensive exercise with calming activities such as gentle yoga, meditation, artwork or other calm activities that spark joy for you.

•       If you’ve done everything above and are still experiencing troubles with your cycle: Consider investigating herbal treatment to help support your body toward hormonal balance while also supporting athletic performance.

Although running and other intensive endurance activity is associated with disturbances in the female menstrual cycle, you can still train hard and keep your monthly rhythm healthy. For some it takes a bit more effort, care and strategy surrounding diet, supplementation and rest. The benefit is worth it: better long term hormonal outcomes along with improved athletic performance and minimal PMS.

Meaghan McCollum ND

www.naturmend.com

References

1.       Roupas ND and Georgopoulos NA. Menstrual function in sports. 2011. Hormones. 10(2):104-116.

2.       Czajkowska M. et al. Menstrual cycle and the prevalence of premenstrual syndrome/ premenstrual dysphoric disorder in adolescent athletes. 2015. J podiatry Adolesc Gynecol 28:492-498

3.       Takeda T. et al. Premenstrual syndrome and premenstrual dysphoric disorder in Japanese collegiate athletes. 2015. podiatry Adolesc Gynecol. 28:215-218.

4.       Moschos S, et al. Leptin and reproduction; a review. 2002. Fertil Steril 77: 433-444.

5.       Rodriguez-Pacheco F, et al, Regulation of pituitary cell function by adiponectin. 2007. Endocrin. 148: 401-410.

6.       Loucks AB, et al. Alterations in the hypothalamic-pituitary-ovarian and the hypothalamic-pituitary-adrenal axis in athletic women. 1989. J Clin Endocrinol Metab 68: 402-411.

7.       Otag A. et al. Effect of increasing maximal aerobic exercise on serum gonadal hormones and alpha-fetoprotein in the luteal phase of professional female soccer players. 2016. J. Phys Ther Sci. 28:807-810.

Marathon Racing Nutrition

Written by Kim Young, RD. 

Kim has been a dietitian for over 15 years.  She’s been competing in triathlons and running events for over 20 years and has been a consultant with a variety of sports clubs.  

You can email Kim at kimyoung.rd@gmail.com or visit http://www.dietitians.ca/Your-Health/Find-A-Dietitian/Find-a-Dietitian.aspx to find a dietitian specializing in sport nutrition to help you develop an individualized training and racing nutrition plan.

Training and preparing for a marathon takes a training plan and dedication.  How you are going to nourish your body to prepare for and complete the event can support your preparation and ensure that you execute you optimal performance.  This article discusses the important points to consider when planning your marathon nutrition racing strategy.   

Carbohydrates

Although many people recognize that carbohydrates are important for exercise, it is not uncommon for marathon runners to underestimate what is required for optimal race performance. Carbohydrates are the major source of fuel during a marathon race.  The sources of carbohydrates that the body uses are muscle glycogen (one of the stored form of carbohydrates in your body) and what you intake during the race.  Other sources of energy that the body uses during the race are fatty acids, liver glycogen and small amounts of amino acids. 

The higher the intensity at which you exercise, the greater the reliance your body is going to have on your muscle glycogen and the carbohydrates you provided it during exercise.  It has been suggested that over 90% of your energy requirements during a marathon race will come from these two sources.

Carbohydrate Loading

Muscle glycogen stores are a limiting factor when it comes to marathon performance.  Increasing the carbohydrates in your diet before the marathon can promote carbohydrate loading of your muscle glycogen stores.  This practice should be done in conjunction with a training taper and appears to benefit men more than women.  Approximately ever gram of carbohydrate stored in the muscle will be stored with an additional 3 millilitres of water.   As a result you can expect to gain a couple of pounds before the race. For this reason some athletes choose to forgo using this pre-race nutrition strategy. 

Over the last few decades several carbohydrate loading protocols have been developed.  The simplest one is to increase your carbohydrate intake by between 8 - 11 grams of carbohydrate per kilogram of body weight per day over 1 - 2 days before the race.  This can be a substantial intake of carbohydrates and translates to about 700 g of carbohydrates for a 155 pound (70 kg) person.  That is the equivalent of about 2 loaves of bread! (Do not consume all the carbohydrates as bread.)

Many carbohydrate rich foods can be a source of fibre.  Increasing your fibre intake the days leading into a marathon is NOT recommended.  Therefore if you choose to try using a carbohydrate loading strategy, you are best to look at using low fibre carbohydrate sources such as sugary beverages, juices, and white grain products.  (On a personal note, I like to buy a bag of hard candies and suck on them over the course of the day or two prior to an endurance event.  I’ve also been known to drink regular pop and order fries rather than having my usual side salad and water with meals during this time.) 

Pre-Race Meal

How much carbohydrate your pre-race meal contains depends on the amount of time between when your race starts and when you plan to eat your pre-race meal.  As a general rule, for every hour before your race, consume 1 gram of carbohydrate per kg of body weight.  Therefore if you are a 155 pound (70 kg) athlete and are planning on eating breakfast 2 hours before your marathon start time, you would try to consume about 140 grams of carbohydrates prior to the race.  It is also important that your pre-race meal leaves you feeling comfortable (i.e. not full and bloated, not hungry) on the start line. 

An example of what about 140 g of carbohydrates may look like include:

·         1 bagel (60 g carbohydrate)

·         1 large banana (25-30 g carbohydrate)

·         1 tablespoon of honey (10-15 g carbohydrate)

·         12 ounces (330 ml) juice (40-45 g carbohydrate)

Race Carbohydrate Intake

Higher intakes of carbohydrate per hour are associated with improved results in endurance events. Historically, carbohydrate recommendations have been between 30 to 60 grams per hour while performing endurance exercise.  More recently, it has been suggested that this limit can be increased up to 90 grams per hour by using mixed sources of carbohydrates, such as a combination of both glucose and fructose.

Race Carbohydrate Intake

Higher amounts of carbohydrates can put you at risk of having gastrointestinal issues if you are not use to taking in this much.  If this is a problem, you may be able to train your gut to tolerate higher carbohydrate levels.  If you are considering trying to push the higher limits, work on doing this during training and slowly overtime.  

It is best to develop your own nutrition strategy using carbohydrate sources that are acceptable to you both from a taste, mouth feel and gastrointestinal tolerance perspective. Often carbohydrate sources are in the forms of sports drinks, gels or gummies/ candies.  Some people choose more whole foods such as dried fruits, diluted fruit juice, honey or syrup.  Whatever your choice is, it is important that you have tried these foods and drinks during training, and ideally in a training race, as intensity can play a role in your personal tolerance. 

Fluids

In the days leading into the marathon, ensuring that you keep hydrated is important.  If you choose to increase your carbohydrate intake in efforts to carbohydrate load, you will require additional fluid.  The best way to monitor your hydration status is through the frequency and color of your urine. A pale straw coloured urine is a sign that you’re well hydrated, but if you take high doses of vitamins, your urine colour may not be a good indicator. 

During the race, consume enough fluid to avoid losing more than 2% of your body weight, but do not try to equal your sweat losses.  A fluid intake of between 400 to 800 ml per hour accommodates most athletes’ needs.  Special considerations include the size and fitness of the athlete, as well as the environmental conditions. Overdrinking (or over-hydration) during endurance exercise is the main cause of hyponatremia (low blood sodium levels).  People who are at the greatest risk for this are those who are smaller, or run a marathon in over 4 hours, therefore often women. 

Sodium

Sodium intake during marathon events is recommended.  The amount needed is highly variable and there is no general consensus.  On average, sweat contains about 1 gram of sodium per litre, but this is also variable among individuals.  Consuming 400 to 800 mg of sodium per hour of exercise is a reasonable range to aim for.  If you are choosing to use sodium tablets during your race, be sure to try them out in a training race or intense long workout. Individuals that need higher sodium intakes include heavy sweaters or those who may not be acclimatized to hot racing environments.

Caffeine

The effect of caffeine is individualized.  How a cup of coffee affects you prior to a race may be quite different than the effect it has on your training partner. If you are planning on including caffeine in your race routine make sure that you have tried it out in practice, and remember that caffeine may enhance any nervous jitters you may experience. Possible benefits of caffeine include increased fat oxidation and less reliance on glycogen stores during moderate to intense physical activity.  In addition, caffeine can have other benefits such as improved alertness, mood and cognitive function.  These are all important parts of a marathon, especially in the later stages.  Research suggests that caffeine intake of about 2 to 3 mg per kilogram of body weight (or approximately 200 mg) before and/or during exercise can enhance performance.

Many sport nutrition products now include caffeine in varying amounts.  If you are considering adding caffeine into you marathon routine, read the labels and do a bit of math to find the right amount for your plan. An example of how you may include it at the recommended doses includes a 8 to 12 ounce coffee about an hour before your race, and using caffeine containing gels during your race to provide between a total of 100 to 200 mg of caffeine over the course of your race.

Hot racing environments

Racing in hot environments puts additional stress on the body.  It is suggested that the optimal marathon temperature is 5 to 10 oC and finishing times begin to increase by about 0.03% for every 1oC above this ideal range, with decreases in performances topping out between 12-17% at temperatures in the high 20oC range.

Nutrition related heat stressors include the body’s decreased ability to use fatty acids or the carbohydrate consumed during exercise.  In addition, there’s an increased reliance on muscle glycogen. Keeping your body temperature down prior to and during the race will help relieve some of this metabolic stress.  Nutrition strategies include sipping on cold drinks, or chewing on ice chips or freezies prior to the race. On the race course, look for opportunities to drink cold liquids, or consume ice or slushies. (Of note, freezie pops were unexpectedly handed out during the 2016 Boston marathon…a nice surprise for those struggling with slightly warmer conditions.)

Planning

Planning your nutrition

What you plan to eat before and consume during your race should be planned out weeks to months in advance of race day.  Ideally, practice your pre-race nutrition before long runs or before less significant racing events.  During exercise and less significant races, practice consuming the forms of carbohydrates you plan to consume during your marathon.  Do your homework and determine how frequently aid stations will be placed on the marathon race course and what will be provided. 

Know that you may not get it right the first time and learn from experience.  If a strategy does not work, evaluate it and reflect on what you will do differently next time.  The more work you put into your nutrition plan the more confident you will be on race day.  This will decrease your likelihood of breaking the rule of not trying something new on race day,  and increase the likelihood you will executing your optimal race performance. 

References:

Stellingwerff T, Cox GR. Systematic review: carbohydrate supplementation on exercise performance or capacity of varying durations. Appl Physiol Nutr Metab. 2014;39:1-14.

Nutrition and athletic performance. Position of dietitians of Canada, the academy of nutrition and dietetics and the American college of sport medicine. Feb 2016. Available at www.dietitians.ca/sports

Spriet L. Exercise and sport performance with low dose of caffeine. Sports Med. 2014;44(Supp 4):S175-84.

Jentjens R, Wagenmakers A, Jeukendrup E. Heat stress increases muscle glycogen use but reduces the oxidation of ingested carbohydrates during exercise. J Appl Phys. 2002;92(4):1562-72.

Jones P, Barton C, Morrissey D, et al. Pre-cooling for endurance exercise performance in the heat: a systematic review. BMC Medicine. 2012;10:166

Tan S, Lee J, The role of fluid temperature and form on endurance performance in the heat. Scand J Med Sci Sports. 2015;25(sup 1):39-51

El Helou N, Tafflet M, Berthelot G, Tolaini J, Marc A, et al. Impact of environmental parameters on marathon running performance. PLoS ONE. 2012;7(5);e37407. doi:10.1371/journal.pone.0037407. Available online.