#PTonICE Daily Show – Friday, September 8th, 2023 – Carbohydrates

In today’s episode of the PT on ICE Daily Show, Fitness Athlete division leader Alan Fredendall discusses the role of carbohydrates, the relationship between carbohydrates & performance, carbohydrate loading, and carbohydrate consumption timing.

Take a listen to the episode or read the episode transcription below.

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00:00 INTRO

Hey everybody, welcome to today’s episode of the PT on ICE Daily Show. Before we get started with today’s episode, I just want to take a moment and talk about our show’s sponsor, Jane. If you don’t know about Jane, Jane is an all-in-one practice management software that offers a fully integrated payment solution called Jane Payments. Although the world of payment processing can be complex, Jane Payments was built to help make things as simple as possible to help you get paid, and it’s very easy to get started. Here’s how you can get started. Go on over to jane.app slash payments and book a one-on-one demo with a member of Jane’s support team. This can give you a better sense of how Jane Payments can integrate with your practice by seeing some popular features in action. Once you know you’re ready to get started, you can sign up for Jane. If you’re following on the podcast, you can use the code ICEPT1MO for a one-month grace period while you get settled with your new account. Once you’re in your new Jane account, you can flip the switch for Jane Payments at any time. Ideally, as soon as you get started, you can take advantage of Jane’s time and money saving features. It only takes a few minutes and you can start processing online payments right away. Jane’s promise to you is transparent rates and unlimited support from a team that truly cares. Find out more at jane.app slash physical therapy. Thanks everybody. Enjoy today’s episode of the PT on ICE Daily Show.


Good morning everybody. Welcome to the PT on ICE Daily Show. Glad to be back again. Hope your day is off to a great start. My name is Alan. I’m happy to be your host today. Currently have the pleasure of serving as the Chief Operating Officer here at ICE and elite faculty in our fitness athlete division. It is fitness athlete Friday. We would say it’s the best darn day of the week here on Friday, live on Instagram, live up here on YouTube, and wherever you get your podcasts. Thank you for joining us. Some announcements really quick. If you’re looking to join us in the fitness athlete division, we have a couple chances online and about a dozen chances live before the end of the year to catch us out on the road. Our online courses, fitness athlete essential foundations, that’s our eight week entry level online course. All things relevant to treating the recreational athlete, the cross fitter, the Olympic weight lifter, the power lifter, the orange theory athlete, the boot camper, so on and so forth. That is the course for you. That starts this coming Monday, September 11th. We still have room in that class. And our advanced concepts course, also eight weeks online. Pre-requisite for that class is essential foundations, our entry level course. Advanced concepts is only taught twice per year. It is taught spring and fall. So this is your last chance to catch it this year. That will kick off the week after September 17th. That class has just two seats remaining. So if you’re looking to round out your fitness athlete certification, make sure that you get into fitness athlete advanced concepts this fall. Live courses coming your way between now and the end of the year. Your next chance will be September 30th on October 1st. That will be out on the West Coast in the Bay Area with Zach Long. Also on the West Coast, October 7th and 8th, you can catch Mitch up in Linwood, Washington. That’s outside of the Seattle area. Also on the West Coast, October 21st and 22nd, Zach will be on the road again, this time up in Vancouver, British Columbia. You have two chances the weekend of November 4th and 5th. You can either catch Mitch down in San Antonio, Texas, or Zach will be down in Birmingham, Alabama. Mitch will again be on the road in November, November 18th and 19th. He’ll be in Holmes Beach, Florida. That’s right outside of the Tampa area on Anna Maria Island. You can catch Joe Hanisco in New Orleans. That’ll be December 9th and 10th. And then our last course of the year will be December 9th and 10th as well. That’ll be out in Colorado Springs with Mitch. So that’s your chance to catch us on the road in the fitness athlete division. Today’s topic, let’s talk about carbohydrates. Let’s take a deep dive into what a carbohydrate is, how it’s relevant to us here in the fitness athlete division as far as exercise, energy and performance goes. And then let’s talk a little bit about when and how to kind of dose out your carbohydrates, who needs to be eating them, who maybe needs to think about eating more. And let’s talk about timing of getting those in to best suits whenever we’re going to be exercising to maximize and optimize our performance.


So starting very basic, if you know nothing, what is a carbohydrate? It is a sugar, a starch or cellulose plant material. So commonly we know carbs traditionally are things made out of maybe table sugar, candy, soda, that sort of thing, potato chips, things that are maybe less than optimal carbohydrate choices but are overwhelmingly what is often consumed when people eat carbohydrates. We also think of fruit being fructose. We think of the sugar that’s in milk, lactose. We also think of carbs as vegetables that we eat when we’re primarily eating the cellulose in a vegetable, we’re eating that plant matter, we’re eating things like green leafy vegetables, broccoli, kale, asparagus, that sort of thing. So different ways we can consume carbohydrates. They’re not all equal as far as content goes, but those are all kind of classified as carbohydrates. Why do we care about them? Well, we really care about carbohydrates because eventually they become glucose in our body, which is an energy currency, a way that we metabolize energy reactions and chemical reactions in our body, but we also store glucose as glycogen. We store glucose as glycogen both in our liver and in our muscles. At any given time, we only have about four grams of circulating glucose in our system. So we have a relatively small amount. Our body does not really like to have glucose moving around in our blood system. So when we tend to get beyond that four grams circulating throughout our body, that’s when insulin is released, insulin is released, and at the end of the day converts that glucose into glycogen, either stored within our muscles or stored in our liver, or if we do have an incredible excess of glucose in our system, it can be also stored as body fat.


Aside from the four grams circulating in our body, we have about 400 grams stored inside of our muscles, and we have about another hundred grams stored in our liver. For most people, a total of about 500 grams of muscle glycogen or about 2,000 calories worth of energy. And that’s kind of where, if you ever wonder where is the recommendation that I should eat 2,000 calories a day to maintain a healthy weight, where does that recommendation come from? It comes from estimations of how much muscle glycogen we are storing and throughout the day using for regular physical activity, but also for exercise. And that if we deplete that glycogen throughout the day, we will need to eat 2,000 calories of food to replenish that glycogen back into our muscles and back into our liver. We can make glucose and then store muscle glycogen on demand. This is that process you may remember back from middle school or high school biology and chemistry called gluconeogenesis, gluconeogenesis, make new glucose. This is a very, very slow energy intensive process. We can only make about 30 grams of glucose per hour. Now this typically comes from our body fat. It’s synthesized, made into glucose, and then is either stored as glycogen or pushed into circulation for energy. So this is kind of where the all day energy you have of being at work, maybe working around the yard, relatively low intensity activity. The energy, the glucose that supports that energy, those metabolic reactions comes from that process of taking body fat, turning into glucose in the liver, about 30 grams per hour.


Now when intensity increases is really our concern in the relationship between carbohydrates, glucose, glycogen, and exercise. That when we start to exceed about 65% of our VO2 max, we start to use more glucose, use more glycogen than our body can produce per hour. So we start to dig into the reserves that are inside of our skeletal muscle and our liver. Now at very high intensities and very long durations, especially if heat, if temperature, is a factor as well, humans can use up to 150 grams or more per hour of that glycogen, which means at any given time, there are only about a couple hours of energy stored in our body for higher intensity activity. So above 65% of that VO2 max, what we call a low oxygen environment, we can no longer make enough glucose and glycogen to replenish what we are burning with that high intensity exercise. We are in a high oxygen environment, relatively low intensity activities. Our body can again make those carbohydrates, make those sugars from the fatty acids from our body fat, but as intensity increases, we start to dig into our reserves. Now that typically happens around the 90 to 120 minute mark. That is going to be a little bit different for every person. Bigger people, people with more muscle can store more muscle glycogen. Those who are better trained, who exercise at all, but especially those who are used to doing long endurance training, can store a little bit more muscle glycogen. And then certainly you’ve heard of the concept of carb loading, where if we taper our activity for two to three days and we increase our carbohydrate consumption accordingly, we can supersaturate our muscles with glycogen as well. And overall, we may have about 50% more glycogen reserves than the average person. We might have maybe 600 to 700 grams available. So maybe we can kind of flirt with having two hours of energy total for high intensity activity before we need to start thinking about eating, eating food, eating it to not only continue exercise, but feel better after, which is part of what we’re going to talk about today. The relationship between carbohydrates and performance, especially if you want to be training multiple times a day or otherwise just not feel terrible the rest of the day after you finish exercise. Now it’s not an all or nothing concept. It’s not, I have a hundred percent of my muscle glycogen or I’ve used it all and I need to stop exercising and eat. We certainly know that we can consume food during long endurance activities, but also that as those reserves deplete, we feel a performance shift as we’re doing different activities of we can feel maybe speed slow down on a run, maybe power slow down if we’re out and we’re on the assault bike or something like that. And we know we can run out. That’s a concept that’s called bonking of where we have depleted almost all of our muscle glycogen and our body is going to take us from that high intensity, low oxygen environment and say, Hey, you need to cool it. We need time to recover some of this energy and your body’s going to stop you for you. And that’s the concept of bonking of shifting you to a high oxygen environment by lowering your intensity in an uncomfortable manner, maybe even possibly losing consciousness, but definitely not feeling like exercising anymore. It’s really important that we never hit that point. If we can avoid it, we’ve all we’ve all done it. I have a story of hiking in the smoky mountains of bonking at the top of a mountain, mainly because my wife ate all of our food on the way up and I had nothing to eat. So I had no choice and bonked at the top. But it’s important to know that we don’t want to get to that point. We never want to use all of our glycogen and hit that wall because there is a compensatory recovery point afterwards where for one to three days after we’re going to feel really low energy as our body slowly recuperates and restores all of that glycogen in our body. We’re not going to feel like pushing the pace. We may not feel like exercising at all. It’s going to impact our training. And what you don’t want to get into is kind of this weekend warrior phenomenon. Where maybe you go you go for a really hard run for two to three hours. You hit the wall and then you don’t feel like exercising maybe for another week, right? Where you don’t feel like you can work out again for a couple of days. That’s not very productive training. So we want to avoid that.


And we’ll talk about that now as we talk about when should I eat my carbohydrates. So it’s really cool that technically a human being does not need to eat any carbohydrates at all. You may have heard of the keto diet of being low carb, maybe no carb, under 50 grams of carbohydrates, being in a state of ketoacidosis of only utilizing your own body fat as an energy source and the fat and protein that you consume. But it’s cool that we don’t technically need to eat carbohydrates. Yet almost all of the metabolic and chemical reactions in our body are fueled by carbohydrates. It’s very, very interesting how our body operates. So you can go without eating carbs. So again, your body can make carbs about 30 grams per hour, but we need to understand that that takes time as we talked about. And especially if we are doing longer, harder events, we’re thinking about maybe training twice a day, something like that. Then we need to understand that that process is slow and we need to give the body either a lot of time or we do need to consume carbohydrates. We also need to recognize at some point that eating carbohydrates is like consuming jet fuel for a mechanical engine. Of it’s a very caustic chemical reaction to our body, a lot like burning gas inside of a gasoline engine, that it does create some low grade, low grade inflammation that’s kind of always present as we’re eating carbs and fueling our chemical reactions with the carbs. And so kind of the longevity side of the research would say, if you want to live as long as possible, avoid that. However, that’s in direct conflict with the performance research, especially if you want to be a more competitive athlete. You want to do longer, more intense activities. You want to maybe train multiple times a day. You need to understand that those are two kind of diverging thoughts of longevity versus performance. At some point, those tend to dissect and not reconverge of needing to eat carbs to fuel your activity, especially multiple activities in a day or a busy workday after you exercise or avoiding carbs. Maybe even you may have a longevity physician who recommends you take metformin prophylactically to keep as much glucose out of your system as possible because of the inflammation that’s present. But nonetheless, we need to talk about that relationship between eating carbs and performance. So it’s that that longevity versus performance question that we have a need to eat carbohydrates if we are a long duration endurance athlete, that when you start to run 10 miles, 15 miles marathon, ultra marathon, when you start to do long trail runs, long bike rides, long hikes, that sort of thing. Again, you are using your reserves faster than your body can make more. And you either need to know that at some point you’re going to hit that wall that we talked about or you’re going to need to start consuming carbohydrates as you exercise. Higher level elite endurance athletes may eat 90 grams of carbohydrates per hour in the forms of liquid carbohydrates, gels, chews, that sort of thing. Folks who maybe are doing half marathon or marathon training may be eating less, maybe about 30 grams per hour. Our fitness athletes don’t necessarily need to eat carbohydrates during exercise. We think about a typical one hour CrossFit class. We’re not really at the level of intensity and duration long enough to need to eat carbs during that hour. We can get away with doing that hour of fitness and then worrying about carbohydrates after. But there’s also a want, a need versus want. The want for carbohydrates is understanding that performance trade off, but also understanding that your body can only make about 30 grams per hour. So what does that mean? That means if you do go to that one hour CrossFit class, you don’t technically need to eat carbohydrates before or during, but that you might want to front load your consumption afterwards, especially depending on the time of day in which you do your exercise. If you’re like me and you like to get up and exercise first thing in the morning and then you might be looking at, hey, I have 8, 10, 12, 14, 16 hour day ahead of me. Those subjective feelings that you may feel your patients, your athletes may feel of, I feel tired all day after exercise. I feel like I just need to go home and go to bed. I feel weak. I feel like I can’t do my work tasks. I can’t take care of my kids. Maybe even feeling lightheaded or some sort of impaired cognitive function. Like my mind just feels cloudy. All of those are good subjective reports to tell you that you should probably eat some more carbohydrates after that exercise session or to recommend that to your patient or athlete. And then we get in now to how to do that of our long duration endurance athletes. We’ve already talked about they’re probably going to be or hopefully should be consuming those carbohydrates as they’re exercising, especially once they cross maybe that one hour mark of again, it’s not an all or nothing equation of go until I can’t anymore of as those reserves of muscle glycogen get depleted, I’m going to feel worse and worse and worse than my performance. And how I get ahead of that is eating, eating those carbohydrates while I’m exercising. So the combination of me eating them and my body making some more keeps them relatively high, keeps my performance, my output higher, keeps me away from feeling kind of that onset of losing power, losing speed, losing energy throughout my workout.


How to eat those? Well, I’m still trying to figure that out. As I get more into long endurance training, I have tried chews and gels and my body doesn’t really sit with those. I tend to do better with liquid nutrition like Gatorade. Every person is going to be different, but definitely those people who are going out for longer workouts, especially crossing an hour need to find a way to start to consume that as they’re exercising. This is also relevant to our fitness athletes who may be doing a multi event day. Maybe they’re doing a local CrossFit competition. Maybe they’re a quarterfinals or a semi finals athlete where they have multiple events per day, multiple days in a row. I always laugh now when I go to a CrossFit competition and I see that person after workout eating chicken and salad, right? Just not enough carbohydrates in that meal to replenish what was used in that CrossFit workout in order to have those reserves restored and ready for the next workout, which might be two to three hours after the first one. They might have a third one two to three hours after that, right? Those are athletes who they don’t necessarily need to eat carbs during the workout because it’s a relatively short event, maybe 10, 20, 30 minutes. But if they have to workout again in three hours, they’re definitely somebody who’s going to want to eat higher carbohydrate food. That’s the case. You see CrossFit Games athletes eating gummy bears and Snickers bars, just getting as much carbohydrates as they can. Again, they’re trying to maybe replenish 200, 300, 400, 500 grams of carbohydrates within a two to three hour window to be ready to work out again. So understanding it’s important to get those carbs back in if you’re wanting to train or you have to exercise again in a relatively short amount of time. I hiked the Grand Canyon last year with Dustin Jones and Jeff Musgrave and we did it. It was about a 12 hour hike up and down about 20 miles and we did it almost exclusively on water, Gatorade and gummy bears, right? Just high carb food that’s going to keep our reserves up because we’re basically hiking and walking in a hot environment at moderate to high intensity for a very long period of time. I’m thinking I just ran 10, 800s this morning. I have a 12 hour day ahead of me. The first thing I did was eat three bananas, right? The first thing I did was house 100 grams of carbs to give my body that jump start on replenishing that glycogen, which was not entirely gone, but definitely mostly gone at the end of that running workout. And that’s really going to determine how you recommend carbohydrate intake to that patient athlete in front of you of what does the rest of your day look like? When do you train and what does the rest of your day look like? If you work out at 5 a.m. and then you have to go to work all day and you’re maybe a physical therapist, right? You have a relatively physically active job. You’re getting your steps in. You have an eight to maybe 10 hour day in front of you. You’ll probably feel a lot better if you eat the majority of your carbs earlier in the day to replenish those reserves. You will find yourself feeling subjectively better. If you work out early in the morning, maybe you run and you want to lift weights at lunch or go to CrossFit after work. How can we fuel our body to be able to do double sessions in a day, two a days, right? The same thing, we need to front load that carbohydrate consumption in the morning, at lunch, in the early afternoon so that by the time we are going to work out again, most of those reserves are back. They’re probably not going to be 100% back where I can PR my 5K in the morning and go PR a CrossFit benchmark in the afternoon. It’s probably not going to work out that way to be 100% ready to go for a second session in the same day. But you will feel better during the day subjectively and you will definitely perform better objectively in that second session if you eat a lot more carbohydrates in between. Now who is that person that maybe works out in the afternoon or evening and that’s their only session of the day and then they go home and they basically watch some TV, get ready for bed and go to bed? That is maybe a person who can get away with maybe a lower carbohydrate or could maybe play with a keto diet, right? Of hey, I work out at 6 p.m. when I’m done with work, I get home around 7.30, take a shower, eat some dinner, go to bed. That is a person that they do not necessarily need to replenish as much of their glycogen as possible because of their schedule, right? They deplete their glycogen in the evening, they are going home consuming some with maybe a dinner meal and then they’re going to bed. They’re giving their body maybe 8 to 10 hours to replenish hundreds and hundreds and hundreds of grams of muscle glycogen overnight while they’re asleep. So that is a person who maybe could get away with lower carbohydrate or no carbohydrate consumption between when they work out and when they wake up again. That’s a person who’s going to work out, have dinner, sleep, have breakfast and have lunch again before they work out again 24 hours later and they’re in a really good position where maybe they don’t need to worry about it as much. So carbohydrates, what, when and how? Understanding they’re very important for performance, especially for longer duration exercisers, for long endurance athletes. They’re definitely linked to performance, especially if you are wanting to train multiple times a day. You are in a competitive environment where maybe you’re doing multiple events in a day and then we need to understand timing of when should I eat them. For most people, if they’re working out in the morning, they’re maybe doing multiple sessions in a day. They’re going to work and they want to feel like they have high energy. They should probably eat a good portion of their carbohydrates earlier in the day, but there is that person who maybe trains later in the day who doesn’t have a lot going on between when they train and when they’re going to train again, who maybe can get away with not eating as much carbohydrates as somebody else. So understanding that food is our friend, food is fuel and understanding how your body creates, consumes and utilizes carbohydrates for energy can be a really big game changer for performance during and after exercise. We all probably have that patient who seems really active, really fit, but complains all the time of being tired, of feeling weak, of not hitting PRs. And that can be a good person, yes, to evaluate their protein consumption, to make sure that their muscles, their musculoskeletal system is recovering appropriately, but also to have a conversation of what their carbohydrate consumption looks like. If we can up our carbohydrate consumption a little bit, we’ll often find that that subjective fatigue, weakness that comes after a training session, especially if we’re going to train again later or we have a long day of work or whatever ahead of us, we can alleviate a lot of that just by tweaking our diet a little bit. So I hope this was helpful. If you’re going to be on an ice course this weekend, I hope you have a fantastic weekend. Have a great Friday. Have a great weekend. Bye, everybody. 

24:46 OUTRO

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