Muscle Cramps

I am asked a lot, "What can I do to prevent my muscle cramps?" I just got my second such question of the day. I wish I could tell people that all you had to do is X and miraculously your cramps will be a thing of the past. Problem is, no one knows for sure what causes cramps. It's unlikely to be sodium (or potassium, magnesium, calcium, etc) despite what you have been told and read your entire athletic life. The research simply doesn't support any of this. But it's difficult to change the minds of hundreds of thousands of people when the sports drink industry spends millions to softly convince you that you just need more salt. I wish it was that simple. If it was I wouldn't keep getting this question. The best I can do is to help educate you about how little we know about this common affliction. Perhaps with a little education you can do a better job of figuring out the cause of yours. What I'd suggest you do is go here, scroll down a little bit, and read the section titled "Muscle Cramps." This is an excellent summary of what is known by sports science currently on this topic. Good luck with your quest for an answer!

Cancer Fund Raising

Very few know this, but back in the late 1980s I was the fund raiser for a non-profit agency that worked with at-risk youth. This is what I did for a living while pursuing my dream to build a career as a personal coach for endurance athletes. Fundraising was a difficult but rewarding job. So I have a soft spot for those who face similar challenges. And I can tell you from experience that it is a huge challenge, made all the more difficult by the present state of the economy, I'm sure.

So you can imagine what I said when I was contacted by Eileen Lee from the National Foundation for Cancer Research who had read my recently posted blog on skin cancer wanting to know if I could help with a fund-raising project. I was asked if I would post a request for your to help. It's painless. I've done it. Will you do it, also?

If you will visit www.coppertone.com and click to take the “Help Strike Out Sun Damage” pledge, Coppertone Sport will donate one dollar, up to $30,000, to the National Foundation for Cancer Research to fund skin cancer research. It will take 3 clicks and 10 seconds on your part. Please do so right now. I appreciate your help. Thanks!

Risk of Skin Cancer

There’s a lot of evidence that regular exercise reduces the risk of the usual killers in western society — heart disease, diabetes, hypertension, obesity, and others. While most of us don’t exercise for this reason it’s still a nice “added feature.”

But there is still one killer that serious recreational athletes are at high risk for contracting – skin cancer. Several hours a week outdoors in the sun makes us more susceptible to developing a skin cancer or melanoma than the average couch spud.

Other factors that make skin cancer likely for those who exercise a lot are fair skin, red or blond hair, older athletes, and a history of sunburns, especially as a child. Also if you freckle after a short exposure to the sun or sunburn easily you are at greater risk.

The best way to prevent skin cancer is to avoid long exposure to the sun’s ultraviolet rays. This means doing your workouts before 10 a.m. or after 4 p.m. when the sun’s rays are most intense. Workout clothing should also be chosen for its sun-protective features. A tightly woven, fabric that covers the back, shoulders, and neck is best. It’s also a good idea to wear a broad-brimmed hat. If possible, exercise in a place where you can avoid sun exposure altogether, such as a gym.

In medical circles there is still some debate about whether sunscreen is effective at preventing skin cancer. Some believe it actually contributes to the incidence of this disease by making users complacent about exposure to the sun. If you use sunscreen choose a sun protection factor (SPF) of 15 or higher, but still limit your sun exposure.

Fortunately, skin cancer responds well to treatment if caught early enough. Using mirrors, check your body monthly looking for changes in mole or skin lesions such as the following:

• Asymmetry. One half of the mole or lesion does not match the other half.
• Border. The edges are ragged, notched, or blurred.
• Color. The mole or lesion’s color is not uniform.
• Diameter. The diameter of the mole or lesion is greater than the size of a pencil eraser.

While melanoma is less common than the other types, it has greater potential for spreading throughout the body.

If you’re unsure whether your skin spot has any of these characteristics it’s a good idea to see your doctor to have it checked. In the mean time, avoid excessive sun exposure.

Webinar

On Wednesday, July 29 at 8pm east coast time Simon Thompson will present a webinar on his secrets to high performance in sport. Simon is an Aussie pro triathlete with a long list of accomplishments including competing in the Athens Olympics. He is also a TrainingBible coach. There is a $20 participation fee. To find out more go to www.trainingbible.com/Webinar_2009July29.aspx.

Real Food & Performance

Have you noticed how food is becoming medicine? Cheerios lowers your cholesterol. Activia yogurt keeps you regular. Milk builds strong bones. We no longer are encouraged to eat food simply because it tastes good. It should also correct some medical condition we have.

There is a similar trend going on in sports nutritional products. Athletes seem to be coming to the conclusion that sports bars, protein drink mixes, electrolyte concoctions and more are healthy and a good source of what we need to improve performance. Athletes comment on such supplements as if it is a foregone conclusion that this stuff is not only healthy, but also the best source of whatever it is we need to become faster and more enduring.

I believe just the opposite: A diet high in such highly processed stuff (I don’t think of them as “food”) is unhealthy. Nature has been making foods such as fruits and vegetables for millions of years. We evolved quite nicely as a species eating these along with animal products. Such foods seem to have everything we need to not only survive as a species but to thrive as athletes.

On the other hand, sports nutrition scientists have been making their stuff for about 30 years. And it’s only been for the last 15 years or so that athletes have preferred to carry a bar in their pocket on a bike ride rather than a banana. Now we’ve come to the point where many (most?) think that the best possible food to eat post-workout is something out of a plastic bag. Some even carry this preference for sports nutritionals into their daily lives eating stuff throughout the day that was unheard of just months ago.

Here are a few guidelines I believe will help you when it comes to making food selections.

• If the product comes in plastic packaging eat it only in very small portions, preferably during exercise, and then only because of convenience.
• If the product has more than five ingredients listed on the package it’s best avoided or eaten in very limited quantities. Eat these only when “real” food is not readily available.
• The foods you should be the most wary of are those that proclaim loudly to be “healthy” or “all natural.”
• Typically, the more expensive a product is per calorie, the less healthy it is.
• The less advertising there is for a food, the healthier it is.
• If your grandparents could not have eaten it, it’s best avoided.

This is not to say that you should never eat sports bars or the like. There are times and situations when they are convenient. But the primary time to eat them is during exercise, and then only very long or very intense workouts. Generally, if you are in decent shape and the workout lasts less than two hours all you need is water, assuming you had a meal sometime in the last few hours before starting the session. For such short workouts you really don’t need all of that sugar or the other stuff (protein, sodium, magnesium, vitamins, minerals, etc) we’re told are some how necessary for sports performance.

For optimal health and sports performance simplify your diet.

"Fit in 6 Minutes a Week?"

When this was posted on the New York Times website...

http://well.blogs.nytimes.com/2009/06/24/can-you-get-fit-in-six-minutes-a-week/

...I got a lot of emails from athletes wanting to know if I thought it was something from which they could benefit. I guess there are a lot of people who have limited time to train. I certainly understand their dilemma. It's a common problem for those of us with jobs, families, and other responsibilities. (An athlete once jokingly told me that he was "sentenced to a 30-year mortgage and three kids.")

The above NY Times article describes a Japanese study in which the researchers had one group of rats swim for three hours on two occasions. Another group of rats was weighted down and put in the water to swim for 20 seconds, 14 times with 10 seconds of rest between "intervals." So one group of rats swam for six hours and the other for just short of five minutes. The article goes on to say that...

"Afterward, the researchers tested each rat’s muscle fibers and found that, as expected, the rats that had gone for the six-hour swim showed preliminary molecular changes that would increase endurance. But the second rodent group, which exercised for less than five minutes also showed the same molecular changes."

I've been unable to find this study so I'm not sure if these six-hour and five-minute bouts were repeated on subsequent days and, if so, for how many days. I also don't know what "molecular changes" are. So there is some mystery about what actually happened.

There's no doubt that intervals are the most powerful training tool available. The athletes I coach do them several times a week. This includes cyclists training for 45-minute crits up to Ironman triathletes preparing for 12-hour races. You can accomplish a lot in a short time with intervals. But the intervals for these two groups of athletes aren't the same. The crit riders are doing very short (12-30 seconds) sprints at maximal effort. The triathletes do long intervals (10-30 minutes) at a moderate intensity (zones 3-4 primarily). This is not to say that the crit racers never do long, lower intensity intervals and the Ironman athletes short, fast intervals. But the bulk of their interval training is similar to the intensity they will experience in a race.

This bings us to the principle of specificity. Basically this says that if you want to prepare your body (and mind) for a specific stressor (like an Ironman race) you need to do things in training that are similar to an Ironman race. But both groups of athletes in my example also do workouts that are dissimilar. For example, the crit riders also do long, steady rides, just not as long as the triathletes.

In the study notice that the scientists didn't give the rats the ultimate test: swim until they drown (I know this is cruel but it's been done by some researchers). I wonder which group would have lasted longer? We also don't know what all was tested for physiological adaptation. Did they measure VO2max? Aerobic capacity might well have been similar for the two groups of rats. But there are many elements of fitness that must change in order to produce a good physical performance.

I doubt if we will ever see someone win Ironman Hawaii after doing 6 minutes of intervals a week, as the article seems to imply is possible.

Should you do intervals? Without a doubt, yes. I have novices do them and they improve rapidly. I also have seasoned veterans do intervals and we always produce positive changes. And if you are short of time, by all means do intervals. One of the fastest ways to increase fitness is to do five, three-minute repeats on a hill at CP6 (your power or pace when at your VO2max) with three-minute recoveries. This session done twice a week will give you a high level of fitness in a few weeks. But there is not just one workout that leads to the highest performance in all events. There are many.

Coffee and Competition

I am frequently asked by athletes if drinking coffee is beneficial to their performance, and if so, how much is needed and how best to time its intake. There is a wealth of published research on this subject. Unfortunately, it is not in complete agreement.

We might start with the disagreement between the World Anti-Doping Association (WADA) and the International Olympic Committee (IOC) on the subject of caffeine as a banned substance. According to WADA’s 2008 listing, caffeine is not a banned substance although it is being monitored. On the other hand, the IOC as of 2008 considers a urine concentration of greater than 12mg per liter to be a doping offense. It would take on the order of 7 to 8 cups of strong coffee in a short period of time for a 150-pound athlete to reach this IOC-banned level. Interestingly, the research that finds a benefit from taking in caffeine in the form of coffee requires far less than this amount.

The research that has shown an ergogenic effect from caffeine [ 2,6,7,10,11,12,14,15] found that an intake of 3 to 9mg per kg of body weight. (about x-x cups of strong coffee) was sufficient. The following are a few examples of body weight intake at this level and a table of common beverages with their caffeine content.

Caffeine Intake by Body Weight for Ergogenic Benefit Based on Select Studies
Body Weight in Pounds (kg) 3mg/kg 9mg/kg
120 (54.5) 163.5 490.5
140 (63.6) 190.8 572.4
160 (72.7) 218.1 654.3
180 (81.8) 245.4 736.2
200 (90.9) 272.7 818.1

Caffeine Content of Common Beverages
Beverage (6oz/180ml) Caffeine Content (mg)
Espresso coffee 300
Drip coffee 180
Instant coffee 165
Percolated coffee 149
Brewed tea 60
Red Bull 59
Jolt 36
Mountain Dew 28
Pepsi One 28
Chocolate syrup 24
Coca-Cola (regular or diet) 23
Pepsi Cola (regular or diet) 19
Instant decaf coffee 2
SOURCES: National Soft Drink Association, US Food and Drug Administration
To determine your intake level to possibly experience an ergogenic benefit find your weight in the top table which shows the intake required at 3 to 6mg per kg. Then look in the lower table to find your preferred drink and how much would be required. For example, if you weigh 160 pounds the range of intake for you would be 218 to 654mg. If your preferred drink is drip coffee you would need to drink 1.2 to 3.6, 6-ounce cups (about 7-22 ounces) to perhaps get a performance-enhancing effect.

I put the qualifiers “possible” and “perhaps” in the above paragraph because, as mentioned, the research is not in complete agreement on the ergogenic qualities of caffeine, especially in drinks such as coffee. Several studies have found no benefit for endurance athletes when using caffeine at the rates suggested above [1,8,16,21]. This may have to do the type of caffeinated products that were used in the studies [13] and the unique characteristics of the subjects such as their habituation to caffeine.

What causes the benefit, if there is one, is not well understood. For years it was believed that caffeine caused the release of free fatty acid stores into the blood thus reducing the reliance on limited glycogen stores to produce energy. But some studies [11,14,15,20,21,23] have not found such an effect. The cause may well be neuromuscular.

In most of the research in which a benefit was found the caffeinated product was consumed about one hour prior to exercise[2,9,11,12,13,14,19], although other studies found a benefit when it was taken in immediately on starting [10] and even during exercise [6,15]. There appears to be no differences in the effects on men or women [14]. Non-users of caffeinated drinks may experience a benefit greater than habitual users [10] but the research is not in agreement on this [18].

For years it was believed that coffee was a diuretic, probably because of the common urge to urinate after drinking it. There is considerable research showing that it does not cause the loss of water or dehydration [3,9,11,17,18]. Of course, the reason you need to visit the toilet is that you don’t drink coffee to satisfy thirst but rather for the taste and physical effects. So, essentially, once your water reserves reach a normal level the excess fluid must be removed.

This article is not meant to be an endorsement ergogenic aids such as caffeine. Whether or not you use a caffeinated drink before exercise is an individual decision. Some athletes consider the use of any performance-enhancing supplements to be a violation of the spirit of sport. If you are not a regular user of coffee or other such drinks realize that it may cause an upset stomach and over-stimulate the nervous system. It can also be habit-forming.

References
1. Anderson, D.E. and M.S. Hickey. 1994. Effects of Caffeine on the Metabolic and catecholamine Responses to Exercise in 5 and 28 Degrees C. Med Sci Sports Exerc 2694):453-458.
2. Anderson, M.E., et al. 2000. Improved 2000—Meter Rowing Performance in Competitive Oarswomen After Caffeine Ingestion. Int J Sport Nutr Exerc Metab 10(4):464-475.
3. Armstrong, L.E. 2002. Caffeine, Body Fluid-Electrolyte Balance, and Exercise Performance. Int J Sport Nutr Exerc Metab 12(2):189-206.
4. Armstrong, L.E., et al 2005. Fluid Electrolyte, and Renal Indices of Hydration During 11 Days of Controlled Caffeine Consumption. Int J Sports Nutr Exerc Metab 15(30:252-265.
5. Armstrong, L.E., et al 2007. Caffeine, Fluid-Electrolyte Balance, temperature Regulation, and Exercise-Heat Tolerance. Exerc Sport Sci Rev 35(3):135-140.
6. Cureton, K.J., et al. 2007. Caffeinated Sports Drink: Ergogenic Effects and Possible Mechanisms. Int J Sport Nutr Exerc Metab 17(1):35-55.
7. Doherty, M. 1998. The Effects of Caffeine on the Maximal Accumulated Oxygen Deficit and Short-Term Running Performance. Int J Sport Nutr 8(2):95-104.
8. Engels, H.J. and E.M. Hymes. 1992. Effect of Caffeine Ingestion on Metabolic Responses to Prolonged Walking in Sedentary Males. Int J Sports Nutr 2:386-396.
9. Falk, B., et al. 1990. Effects of caffeine Ingestion on Body Fluid Balance and Thermoregulation During exercise. Can J Physiol Pharm 68(7):889-892.
10. French, C., et al. 1991. Caffeine Ingestion During Exercise to Exhaustion in Elite Distance Runners. Revision. J Sports Med Phys Fitness 31(3):425-432.
11. Graham, T.E., L.L. Spriet. 1991. Performance and Metabolic Responses to a High Caffeine Dose During Prolonged Exercise. J Appl Physiol 71(6):2292-2298.
12. Graham, T.E., L.L. Spriet. 1995. Metabolic, Catecholamine, and Exercise Performance Responses to Various Doses of Caffeine. J Appl Physiol 78(3):867-874.
13. Graham, T.E., et al. 1998. Metabolic and Exercise Endurance Effects of Coffee and Caffeine Ingestion. J Appl Physiol 85(3):883-889.
14. Graham, T.E. 2001. Caffeine and Exercise: Metabolism, Endurance and performance. Sports Med 31(11):785-807.
15. Kovacs, E.M.R., et al. 1998. Effect of Caffeinated Drinks on Substrate Metabolism, Caffeine Excretion and Performance. J Appl Physiol 85(2):709-715.
16. Lamina, S. and D.I. Musa. 20008. Effects of Two Levels of Caffeine Doses on Endurance Performance of Normal Young Black African Subjects. Doping J 5(1): http://dopingournal.org/content/5/1/
17. Millard-Stafford, M.L., et al. 2007. Hydration During Exercise in Warm, Humid Conditions: Effect of a Caffeinated Sports Drink. Int J Sport Nutr Exerc Metab 17(2):163-177.
18. Paluska, S.A. 2003. Caffeine and Exercise. Curr Sports Med Rep 2(4):213-219.
19. Robertson, D., et al. 1981. Tolerance of the Humoral and Homodynamic Effects of Caffeine in Man. J Clinic Invest 64:1111-1117.
20. Roti, M.W., et al. 2006. Thermoregulatory Responses to Exercise in the Heat: Chronic Caffeine Intake Has No Effect. Aviation Space Environ Med 77(2):124-129.
21. Roy, B.D., et al. An Acute oral Dose of caffeine Does Not Alter Glucose Kinetics During Prolonged Dynamic Exercise in Trained Endurance Athletes. Eur J Appl Physiol 85(3-4):280-286.
22. vanNieuwenhoven, M.A., et al. 2005. The Effect of Two Sports Drinks and Water on GI Complaints and Performance During an 18-km Run. Int J Sports Med 26(4):281-285.
23. Wemple, R.D., et al. 1997. Caffeine vs. Caffeine-Free Sports Drinks: Effects on Urine Production at Rest and During Prolonged Exercise. Int J Sports Med 18:40-46.

Origins of the Training Bible

Recently I was interviewed by an Australia cycling magazine that was interested in the the origins of the Cyclist's Training Bible. Here is the transcript...

Q. Have you been surprised by the success of 'The Cyclist's Training Bible'?

A. Yes. When I started writing it back in 1994 my only purpose was to put on paper what I did with athletes in order to see if I could explain it and in the process better understand my own methods. I thought it would sell maybe 5,000 copies over the next 7 years and that would be the end of it. It sold that many in the first few months. I was astonished.

Q. Given that 14 years have elapsed since the first edition, what have been the most significant changes in cycling over that period?

A. Training for cycling has become much more scientific. I had always approached training that way but never really knew of anyone else who also studied the science of training for the sport. Now it seems most everyone, athletes and coaches, have a much better grasp of the science behind high performance.

Q. While appreciating that the Bible may have started off its life as a training tool for the serious cyclists, have you noticed any shift in readership - an increase perhaps in the numbers of recreational riders who want to up their performances?

A. I get emails from riders from all over the world who tell me that they have used it to ride faster centuries, ride stronger with their local group, or just be more fit. I never expected non-racers to have an interest in it.

Q. Is it possible for recreational riders to lift their performances, to become more bike-fit by reading your book?

A. Yes, there's no doubt. Any time someone is interested in being more fit in order to ride faster they will benefit from doing much the same stuff that high-performance racers do.

Q. Can you provide us with a couple of the highlights of your career as a coach?

A. One of the things that has always excited me is to see novices begin to succeed and realize they are becoming competitive athletes. I'm working with an older woman now who is in her first full season of racing. She is making great progress yet still has a long ways to go. This is one of the things I find very exciting. The other is consulting with athletes who race at the highest level. They have unique needs and I find it very fulfilling to help them excel also. There have been many athletes in both categories.

Q. What spawned your interest in cycling?

A. I started out as a runner in the 1970s. Then I took up triathlon in 1983.
And shortly after that got involved in cycling also. My son, Dirk, played a big part in that final shift as he was starting to race at about the same time--early 1980s.

Q. How did your career begin?

A. I was a high school track coach in the 1970s. In the mid-1970s I got my masters in exercise science in order to improve my own racing. I decided to leave teaching and open a running store in 1979. Then in 1983 I bought the bike store next door. While operating these stores people would come in to talk with me about how to train for some event since they knew I had a degree in that area. Next thing you know I was coaching dozens of people. By 1987 I realized I liked coaching more than retail so sold the businesses. I have been coaching ever since.

Q. Your son Dirk became a professional rider - is it something that's in the genes?

A. Science tells us that endurance comes from the mother. Not sure what I contributed. And actually I'm not sure who the mentor is - Dirk or me. We're kind of like a team.

Q. Were you from a cycling background?

A. No. My father and mother had no interest in sport. They grew up in the Depression years and had very hard lives. My father was the primary bread winner in his family starting at age 13. I became interested because of a coach I had in high school back in the early 1960s.

Run Pacing

I recently came across some interesting data on pacing of world records in endurance running events on the track. It indicates that nearly all of the record-breaking times in the last 40 years or so have been run with negative splits. That means the second half of the race was run faster than the first half. This, of course, has to do with the pacing strategy I write about so often—holding down perceived effort early in the race rather than starting out of control and then limping to the finish.

Here is the basic data I refer to...

Between 1967 and 1998 the men’s world record for the mile was broken 10 times. Of those 7 were negatively split, but just barely. The average first half time for all 10 was 50.3% of the finishing time (+/- 0.53%). In other words, on average, the first halves were run more slowly than the second halves of the race.

Same thing here. From 1966 to 2004 the men’s 5000-meter world record was bettered 13 times. Twelve of those were negative splits. The average first half was 50.3% of the finishing time (+/- 0.71%).

And finally, the men’s 10,000-meter world record was broken 14 times between 1977 and 2005. Of these 11 were negative splits with the first half being run in 50.2% on average of the finishing time (+/- 0.22%).

The bottom line here is, once again, that if you want to run a fast race it appears to be beneficial if you start conservatively and pace yourself so that the second half is run slightly faster than the first half. Of course, this assumes that the course is flat and wind is not an issue. That is seldom the case, So the better way to think about this, given that terrain and weather may well be issues in pacing, is to focus on perceived exertion. Run at a lower effort than what you feel like you could do in the first several minutes and you greatly improve your chances of a negatively split race.

I tell the people I coach that when a running race starts, if they aren’t being passed by nearly everyone who started around them then they, too, are going too fast. I tell them to be patient and have confidence that they can finish stronger—and race faster—if they merely hold back a bit at the gun. Nearly all of those who passed them will “come back” later in the race. And it is very stimulating when this happens. Passing others late in the race keeps you focused and racing aggressively.

The problem is that most runners can not control their emotions at the start. If the person next to them is going too fast at the start then it is assumed that is the proper pace. You’ll never realize your potential as a runner until you learn how to develop and follow a pacing strategy. This requires both mental control and physical practice.

Question on Sports Drinks

I just received a great question from a coach about what he should tell the athletes he coaches about sodium and protein in sports drinks during long events such as Ironman. Here is my reply...

***********************************************

I’ve been doing a lot of reading in the literature and talking with informed people regarding, especially, sodium. I’m coming to the conclusion that sodium is not necessary during exercise for all of the reasons we have previously been told were so critical - cramping, coping with heat, and maintaining pace/power. I can find no good evidence to support any of these. Just a lot of opinions and sports drink marketing stuff (which most athletes have come to accept as factual).

That said, sodium is beneficial in the transport of water across the intestinal mucosa in the upper intestine where it is absorbed. In other words, with a bit of sodium in the drink you get more water into the body. That may be beneficial to performance if there is a real risk of excessive dehydration (which is far too often blamed for poor performance). As I’ve mentioned before, the most dehydrated athlete in the race is typically the winner. But this is a whole other discussion.

Is protein necessary or even beneficial in a sports drink? The research is murky on this still. However, there is something called “central fatigue” which has to do with the central nervous system experiencing the need for sleep during extended exercise. This seems to be related to circulatory branched chain amino acid status. A couple of studies have suggested that taking in protein during or before exercise may prevent this. But the condition seems to be quite rare. Interestingly I spoke with an athlete a few days ago who did an Ironman and felt like he just wanted to lay down beside the road while in the bike leg and take a nap. This may have well been central fatigue.

What do I do? I eat well before starting a workout. Then I drink water only when thirsty on very long rides and carry carb products such as gels and bars in my pockets. They have a small amount of sodium and negligible protein. Water-only works fine for the first two hours on long, easy to moderately hard rides for me. Then I start taking in carbs along with the water. For example, last week I rode over 500 miles in the Colorado mountains with thousands of feet of moderately hard climbing every day. The average duration was nearly 5.5 hours a day for 6 days. I did just what is described above and never experienced the least bit of problems.

But that was an n=1. Individual athletes may well have unique needs I don’t have for any number of reasons. Some experimentation (with an open mind) is necessary to discover what works. The problem is that most athletes have been so inundated with marketing hype (much of it from “science”) that they can no longer think critically.

I tell the athletes I coach that if they want to use sodium during exercise that’s alright. I know of no downsides (although there may well be some we don’t know about yet such as balancing potassium and sodium, and inter- vs intracellular fluid levels). The same goes for protein. It’s up to them if it has worked ok in the past. If they have had digestive tract problems such as nausea or the gut “shutting down” then I suggest omitting the protein.

Generally, I have come to believe that we need far less “stuff” in our guts during exercise than we have come to believe over the last 30 years. The only two things that seem to stand the test of time are water and carbohydrate. And it’s quite possible to be excessive with both of these.

I hope this helps a bit. I wish I could tell you without question that what I’m suggesting here is irrefutable. It’s where my head is right now on this subject. Time marches on.