Dangers Of Too Much Sugar For Endurance Athletes? | GTN Coach's Corner

Is there an optimal gap between races? Should you listen to your watch for recommended sessions? I missed sessions from being ill, how should I make up for them? Is there a danger of too much sugar as an endurance athlete? Mark answers your latest #GTNcoachescorner questions.
Welcome 0:00
How much time should I take between races? 0:38
Garmin always asks me to run too hard 2:40
Should I catch up on sessions or take a step back? 4:12
Training with limited swim time 5:42
Is sugar bad for endurance athletes? 7:50
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[@gtn]

What are your go-to snacks on race day? 🤔

[@saheedshabbir]

Snickers or Twix

[@Persistence_run_444]

Pinole and chia seeds. Yep. I read Born to Run. Lol

[@_Zabamund_]

Veloforte gels

[@alisontriathlonlover]

Gels , bars & sweets not very original I know 😂

[@svdb2981]

90% gels from the action. But they dont have them anymore. For training. Now i switched to gels from the eatos. And for real test I use more expemsive gels.

[@makebreakrepeat]

I distinctly remember towards the end of my first ironman picking up a cup of hot broth from one of the stations. After a day of gels and chews and bars it felt like my body was thanking me. Since then I've always tried to have a little bit of real food in the plan.

[@Underdog_Triathlete]

Yooooo, thanks! Really appreciate y’all addressing my question. I had a feeling I needed to bite the bullet and just start giving my body the fuel it needs (sugar or no), but it really helps to hear it from someone else too-and the resources are a huge help too. Y’all are the best!

[@gtn]

You're welcome - happy training!

[@inz_uzi]

You do not need to be worried about sugar. The simple sugars vs complex carbs is in my opinion just BS. It really doesn't matter if you eat the most complex carbs on the planet because in the end they can only be absorbed as simple sugars. Starch is broken to glucose. The complex carbs are digested a bit slower but in the end it doesn't matter much because it elevates blood sugar anyway and it triggers insulin release which if done on every meal over the years it may lead to type two diabetes. If you want to prevent the sugar spikes you need to consume carbs with fat and proteins. Especially proteins slow down the sugar absorption. As for fueling while training you do not need to worry about the simple sugars at all because your muscles will burn it on the go. If you aim for 80 g per hour on 5 hours rides I suggest to forget about any sports gels and bars. It's way too expensive. I use table sugar instead. It has 1:1 glucose to fructose ratio and the "magic" 1:0.8 ratio is just marketing. I dissolve it in hot water (makes it easier) and add some electrolytes. I put it into a soft flak, sip from it every ten minutes and rinse my mouth with plain water from my bottle to get rid of the sweet taste. I've been doing this for a few years without any issues. Much cheaper and does the same job. Don't believe in sport products marketing. It's a rip off. If you really think you need maltodextrin with some specific ratio to fructose you can buy these ingredients online for 10% of the price and make your own mix from it. Good luck 😊

[@Underdog_Triathlete]

@@gtnAbsolutely, and you too! 💪 I can tell already that more adequate fueling is helping me reach new highs, and I’m loving the process. Now I just have to wonder what all those carbs & simple sugars are doing to my teeth…🤔 but maybe that’s a question to submit to GTN Dentist’s Corner instead! :P🦷

[@stephenlandrum2262]

Yeah so with the bike portion of a Ironman, would it be totally frowned upon to eat an entire Sam’s club $8.99 pizza?

[@gtn]

We normally celebrate with Pizza but if it works for you...we guess it's perfectly acceptable 😅

[@alexgeorge7473]

Cheaper than a Maurten gel

[@gourami7]

​@@alexgeorge7473Might be better tasting as well

[@danmwilson911]

I'd call that winning!

[@marypagones6073]

Sounds risky--the hot grease might make your gloves a bit slippery!

[@SheriffsSimShack]

I'd recommend using garmins daily workout recommendation with heart rate and not with paces. I give in a hilly area and garmins pace recommendations are absolutely no help for me. Just use it with heart rate.

[@BethanyBlount]

Regarding the swim question, this is similar to the situation I was in when I started seriously training for triathlon. I didn't live quite so far away from my pool, but the lap swim time was similarly late. I went one day a week, had everything I needed ready to go for during and after the swim, and wouldn't train the following morning to help balance out my sleep. The next day was usually something easier (physically, mentally, or both) to give me another day to recooperate after less than ideal sleep. My goal for the session was to get there and be ready to start my session as soon as I was allowed in the water (doing a dryland warm up if necessary). This pool had benches off to one side, so I'd leave my recovery drink there and start drinking as soon as possible. It was tough but worked for the six months I needed it to. I feel like this is feasible because swimming is so technique driven. I made sure one of my gym days also included swim focused lifts.

[@mottohorn]

5:41 I appreciate this advice. As a cyclist and former runner (I have yet to get into the swim), I just got sick in California with something flu-like over the weekend perhaps from not cleaning my bottles well enough after a century ride the week before. I just finished a 14 week long winter base training plan too, so it’s good timing I guess. I will take a little break to recover athletically and get back to making improvements soon! I do enjoy getting better!

[@djdelprado]

great tips guys! thank you!

[@gtn]

Any time!

[@lizzobeach5179]

Amused by the shoes James was running in whilst talking about the watch guidance -> hanging behind Mark… 😂

[@lukegoss2119]

The only way to know if you are eating too much sugar is to get an HBA1C blood test (GP can order or it or cheap to get it privately).It tells you what the blood sugar average is for the past three months. If it's in the normal range you know your current carb/sugar consumption is okay. If it is pre diabetic it is worth reviewing things. I think it's worth doing the test at least once a year if you are on a high carb diet, or even if you're not.

[@dan-312]

Or better yet, get an insulin test. That # going up can often help you see a decade in advance the path your on. You'll know that sugar-based fueling is causing deep down damage to your metabolic health. Might be time to build your fat-burning engine instead of carb-burning.

[@iggalan]

#GTNCoachesCorner Hey GTN, I have a question regarding heart rate zones. I have left my zones in auto mode in my Garmin and currently they are max 183, rest 45. For context I’m 51 years old reasonably fit. During some interval sessions I’ve hit over 192 easily, so I don’t think they are right (using a chest strap). Also last Sunday I did a marathon and looking a the zones, I spent 32 minutes in zone 5 (>168), 2h14 in zone 4 (155-168), 57 minutes in zone 3 and nearly no Z2 or Z1. This doesn’t sound right, does it? Thanks!

[@luisgil5699]

#GTNCoachesCorner hey! Thanks for such great content. I really appreciate as a new guy on this Triathlon journey. I have a question regarding seat. I’m coming from Road race back ground and now with a TT bike I went to my trusted biomechanics for fit and everything goes great except the seat. I have a Pro Stealth seat with middle hole but now I’m experiencing a new level of hurt on my insight area 😂 do you recommend a special TT seat or other strategy?

[@KwyjiboVanDeKamp]

@Muddadeine31 On some Garmin watches you can decide whether your training by pace or by heart rate. I would recommend you to set it to heart rate so you're not overpacing.

[@WarHammerWH]

Thanks for the video. I’ve also asked myself how much increased intake of sugar should be considered. You mention that since it’s being used in an endurance event we shouldn’t be overly concerned about it. However, the liver still has to process all that sugar so couldn’t this overtax the liver and in the long run lead or at least contribute to insulin resistance?

[@Ivan_Nano]

Wow. I asked that sugar question three times on coachescorner and never got answered. Happy it got answered finally even if it wasn’t for me. One added question about it: if you consume that much sugar, what about the insulin release and making the pancreas work harder? Isn’t that what eventually ends up in diabetes? Wouldn’t it make you insulin resistance? Or by burning it out the pancreas is not involved?

[@mrbean3352]

Diabetic but athletic

[@KirubelEshetu-jy1me]

Always everything in moderation is good. Not a sports pioneer like you my brother Mark, but balanced sweets are crucial to healthier diet and fitness! My best wishes to you. Kir of Australia 🇦🇺

[@maxine6828]

#GTN coach‘s corner Hello GTN Team, thank you for your brillant content. I have a question: I have a Sprint Triathlon race coming up in the middle of May. I did one before. For the first time I do train with a structured training plan which I downloaded online. It works wonders so far as my fitness improved massively in a short time. The plan runs for 12 weeks. Sadly, I started my plan too early, bacause the race date was not known a few weeks ago. So now my plan ends two weeks before my race and includes and easy week right before the race. Surely, just stopping the training right then is not useful. But how shall I fill the two weeks that are now missing? My plan is structured into base training, then increase of specific endurance, then race specific Training, 4 weeks each. Shall I just extend the race specific training by two weeks? Happy about any tip on what makes sense and how to approach this. Thank you!

[@MichaelZ-1]

#GTNCoachesCorner as a 42 year old, I’m restarting to pick up triathlon after 15 years. I never was a high flyer, but now I want to try to put some weight behind it and go for the best I can. I’ve got two kids who I want to inspire that you can do a lot (everything would be nice, but hey, that’s a dream not reality) if you put your mind to it. So, this year I want to do three sprint distances of a very small local competition and try to get a good performance. I am training regularly but speeding up is hard at this age (came more naturally when I was around 25). So I think I need to work on technique as well, what would you recommend? A coach is quite costly and most I can find don’t seem to be focussing in technical aspects, but I could be wrong. Maybe trainers in one of the three sports? And tackle one sport at a time? Maybe workshops/courses on one of the sports? Thanks for the lot of information you provide, you are awesome (also everyone behind the scenes putting it all together)!

[@gustavnissen3384]

#GTNCoachesCorner Hello gtn:) I am in the middle of doing the final gear shopping for my full distance Ironman in August. I was wondering if it is worth buying an aero tt- helmet. Right now I am rocking a standard specialized align ii helmet, but I am interested in how much time (if any) a more aero helmet can save me over the 180km? Best regards from Denmark🇩🇰

[@jamiefuhrman403]

#gtncoachescorner As a follow up to the seemingly popular question about missing / making up training sessions, I have my A race full distance planned mid August. I will be on vacation for a week in early July when I have two key long bike and run sessions scheduled and will not have pool or road bike access. I will have access to a spin bike. Would it be beneficial trying to do my key bike workouts on the spin bike, or should I focus on a run and cross training heavy week instead? Should I try to do the key bike workouts before/after I return?

[@mikeanderson3076]

#gtncoachescorner In 4 months I will be participating in my second Swissman Extreme Triathlon. I am 57 years old and participated in the race in 2022. I missed the cutoff at mile 18 of the run by 15 minutes and the bike took me 10 hours to complete. I'm hoping to shave at least 1 or 2 hours off the bike and looking for advice. What is the best gearing for climbing 12K feet in 112 miles? And, how should I balance endurance bike training and power training in the months leading up to the race? Thank you!

[@lizaho246]

I did a full distance Tri 5 weeks later for ironman Wales 😬 it's my 2nd year of Tri ...I managed a 12 hour outlaw and got 3rd age group .. ..ironman I finished under 14 hours but I wouldn't do that again 🤣 the day after ironman I got COVID and it took me months to recover from that and the 2 races pretty much back to back ...🤦

[@KramerX69]

Hello GTN team! Since starting my triathlon journey in 2022 I have lost about 18kg (40lbs)! While I feel great and have continued to improve over time, I feel that I am approaching the lower limits of a good weight is for me. As we come into a new outdoor season with longer training sessions and more calories burned, what are some tips for maintaining a good weight and making sure that all important muscle mass isnt being lost? #GTNcoachescorner

[@NickActive]

Great question.

[@maniastrat]

Yes it seems common enough sense that we need energy but to say so that is ok to take on loads of sugar may or may not be short sighted. Yes you get the energy but what long term studies have been done to see how it affects the arteries of older endurance athletes who have been fueling that way for years/decades? Has it caused inflammation of arteries? Insulin resistance? Carotid Stenosis? High Calcium Heart scans? Diabetes? Where are these tests? I do not think the gel / sports hydration etc companies will be showing these anytime soon eh? Maybe not even magazines & websites that get dollars thru advertising

[@nataliamartinkova]

Hi #GTNCoachesCorner! How do you distinguish being tired because of not eating enough and being tired because of the effort duration?

[@user-yo4js7vc7v]

#GTNCoachesCorner Hi team, any ideas why my interval training pace does not seem to translate to race performance? I can comfortably do 5 x 1km at sub 4.00 min/km pace (With 60 seconds rest). But try putting 5km together and I blow up after a couple of Km. many thanks for any pointers you can offer

[@marcuswills6569]

Your 5 x 1km intervals should be run faster than your 5km race pace if that makes sense.

[@user-yo4js7vc7v]

It does thank you. So for a 20min 5k, each rep needs to be in the area of 3.50 min/k pace or faster?

[@AlexanderLeven]

#GTNcoachescorner Hi there, i have a question related to HRV. Until now i had a HRV in the range of 45-55 and all my daily values were normal. Low when i was ill and up when I have been feeling well. But never over 55 and mostly within the range. Now i have been ill 2 weeks ago and have been ill 2 weeks ago and as predicted the rate went down. However, since recovering this weeks values are sky high. Over 70 and average 20 higher than my range of the last 2 years for 7 days in row now. I have several theories "from the meds killed another underlaying Virus" to "my chronic overload is finally balanced by the time out" but i am afraid that it is "another illness"? I feel well, my training load is still relative low and stress is higher than normal but not abnormal high. What is the most likely cause of those high values? Thank you very much!

[@thegoodguy2424]

#GTNCoachesCorner what percentage of your long run or bike take up of your weekly mileage? As of now my long runs/bikes typically make up just under half of my total for the week.

[@jayhoughton4174]

What data are you putting in other than heart rate, which is captured by the Garmin? Your answer seems to blame user error rather than the Garmin system

[@TamaEnergy]

My dentist says the gels are awful...

[@markoljustina]

i have the same feeling

[@nockee]

It’s really not that hard to take on 100-120 grams an hour on long hard rides. I feel they overdo the “pros have carefully worked up to their levels” stuff. It completely changes how long rides feel.

[@michaelvrbanac6923]

Good advice on IM full and half for prep. Garmin wrist HR is fine when not training. Get a chest strap for training. HR wrist based can be way off when training. Good advice on no catchup. Applies to minor injuries and sickness. Don't wait on swim training. Do dry land exercises, and there are swim trainers if you can afford and have space. No, you don't need carbs during training and racing if you adapt. You can get type 2 diabetes. There are IM athletes that don't eat during racing and training. They are keto. Water and electrolytes. Sugar is bad, period. GTN: you need to do some homework on sugar. Your body is getting rid of glycogen and carbs because it doesn't want them. Muscles burn fat. See multiple sources including Professor Timothy Noakes. Your body may need some carbs during racing and training if your liver isn't making enough for your brain. Anthony Chaffee has a good high level podcast on nutrition too. See Timothy Noakes Foundation website too. I am keto/carnivore, and I take a small amount of carbs during IM's for insurance as to brain needs.

[@peterfagan559]

With the T100 starting soon. Can you guys let us know how to watch in europe.

[@marcuswills6569]

Eurosport will likely have it

[@user-kn1wi3oh3o]

How to do triathlon from 0 and small budget, cause you have to pay trainer, expensive bike etc

[@gtn]

We understand that as a sport if can be pretty full on and expensive, we did a triathlon on a budget to help point you in the right direction 👉kzbin.info/www/bejne/qGmpqIZ9htNropY

[@aliasgharkhoyee9501]

Fat is a much better source of fuelling, except for seriously high intensity work. Fat reserves are 10x higher in most people, you avoid blood glucose spikes & crashes, other long-term diseases like diabetes & cancer, and it's much more efficient - you can keep going for hours or even days with a small amount depending on the activity. Some naturally occurring carbs like veg & fruit are an exception. It's true that some drawbacks of sugar intake are minimised if you're actively using it (vs on the couch) but if you have a choice go for healthy fats (like nuts, cheese, yoghurt, olive oil & butter, not processed veg oils). Unlike carbs, some fats are crucial, your body can't make them by itself (essential fatty acids). It takes a few days to weeks for your body to adapt so don't switch 100% on day 1, but once you're on the other side your health & wellbeing in general goes through the roof. It's the best antidote to the modern high-sugar & processed lifestyle, which causes weight gain. Using higher fat foods instead keeps you satisfied for longer, so you end up eating less and this eventually gets rid of excess weight.

[@nickc4716]

You’re conflating at rest/non athletic advice with advice for carb use during exercise. There might be a tactical benefit to fat burning if access to food during the event will be restricted, such as self supported ultra distance running perhaps, but if access to carbs is plentiful in an event or training then why deprive the body of it’s preferred fuel source. There’s a reason pro athletes are all working to increase the amount of carbs they can use in races. At least in aerobic endurance sports.

[@Panagiotis-Skordilis]

so tell me, what fat i can take with me on a brevet of 400km

[@richardmiddleton7770]

​@Panagiotis-Skordilis MCT oil or regular coconut oil. You have tens of thousands of calories worth of fat already stored though!

[@Panagiotis-Skordilis]

@@richardmiddleton7770 i can't understand really. What is the benefit of that instead of carbs?

[@jamiefuhrman403]

This is called ketosis and works for some people. The reason most of the science supports carbs for fueling is exactly because of the fat reserves you mentioned. Your body has far more fat in reserve than carbs, and carbs are digested and turned into energy quicker. Thus, fueling with carbs tops of your more limited glucose storage. The longer and slower the event, in general, the more likely you are to be able to fuel effectively with low carb / high fat.

[@markankone9362]

Are there runners or cyclist who are have experience on long distance white a gastric bypass surgery and sport nutrition? Mark

[@Thezuule1]

Not personally but a gastric bypass shouldn’t affect your ability to eat gels and drink sugar water.