Author: Colleen Gulick, Ph.D (ExPhys), MS, BS (BioE), EIT (ME), CSCS
When and how to fuel your indoor workouts.
2020 was the year of the indoor bicycle. The pandemic had bikes flying off shelves and programs like Peloton, Zwift and TrainerRoad logged millions of new users. The months confined to our homes resulted in exercise enthusiasts pedaling countless miles in the saddle. Whether you are a HIIT or endurance rider, the luxury of indoor bikes provides easy access to a workout regardless of the time of day or the weather outside. Cycling without battling traffic, stopping at lights, and changing flat tires is a welcomed addition to the living room. Plus, you can quickly squeeze in a workout before your next Zoom call or while watching the kids. This allows you to be incredibly efficient. You can further enhance the value of your workout by following some easy nutritional guidelines. Here’s how you can fuel to enhance your next indoor ride.
What should I eat/drink BEFORE?
The intensity of your workout will dictate your pre-ride needs. If you are planning a low intensity ride (e.g. a “low impact” Peloton ride), you won’t need to eat anything since your endogenous fat stores will fuel your ride. Fat is an efficient fuel source; however, it can only be used to power low intensity activities.
If you are planning a high intensity ride (e.g. a Zwift race), riding on an empty stomach can hinder performance. Glucose and glycogen (which is the stored form of glucose) are used to power sprints and high intensity efforts. So, if you are on a low carbohydrate diet, are fasted, or simply did not eat breakfast, then your glucose (and potentially glycogen) stores are probably low. If you try to perform a high intensity workout under these conditions you simply won’t go as fast (or produce as much power) because your muscles are not getting the fuel they need. It’s like putting a governor on your motor. When performing high intensity exercise in the absence of carbohydrates, you will only be able to go as fast as your fat stores allow. To remove this governor and go your fastest, you can eat a meal containing carbohydrates 3-4 hours before your ride. To top up glucose and increase available fuel, eat additional carbohydrates within 45 minutes of working out. A few examples of easy to digest sources of carbohydrates are: sport gels, Jell-O fruit cups, gummy bears, rice cakes, cereals, bananas, and oatmeal.
Indoor cycling presents some unique challenges with regards to hydration. When cycling outside the natural wind aids in the cooling process. However, when indoors the climates can dramatically vary between training set ups. Ideally, you would have a fan to cool you, a towel to wick moisture, and a cool temperature. Unfortunately, living rooms and basements are not usually equipped for the ideal training environment. In order to prepare for your workout, hydrate with 14-20 oz of water with added electrolytes two hours prior to riding. If you have an early morning ride then do your best to drink before getting in the saddle. The goal is to drink enough to start the ride hydrated and stay hydrated even as you begin to lose water (and valuable electrolytes) via sweat throughout the workout.
What should I eat/drink DURING?
In addition to intensity, duration of a ride also impacts fueling needs. Although Peloton workouts can range from 5 min to 90 min, the majority of the classes are 30-45 min. (1). Zwift, on the other hand, tends to have users that are more experienced cyclists. Thus, the rides tend to be longer in duration on Zwift.
Low Intensity, any duration
Scientifically, low intensity rides can be identified as rides in which you are working at less than 60% of VO2max (the maximum rate of oxygen your body can use during exercise). However, don’t worry if you do not know the numbers that correspond to your VO2max. A simple way to identify a low intensity workout is the ability to easily have a conversation while riding. If you can chat while you pedal then no additional food is needed during your ride (nor will it enhance performance). Any energy needed to complete your workout is provided from what is already in the body stored as fat, especially if the exercise is short (<45 min). If there are a few sprints interspersed that are of a higher intensity, your endogenous glycogen stores should be able to handle these short bursts of energy.
Even though food is not required for this intensity of workout, hydration can have a huge impact on performance. Losing 2% of your body weight in sweat during the workout can reduce athletic performance by up to 10%. In order to avoid this deleterious outcome, stay hydrated by drinking throughout your ride. Do not wait until you get thirsty to drink, by the time your body signals the thirst sensation you are already mildly dehydrated. When you sweat you lose water and valuable electrolytes (in a 4:3:2:1 ratio of potassium: sodium: magnesium: calcium, respectively). Replenishing these electrolytes helps to maintain your fluid balance, regulate blood pressure, and support muscle and nerve function. Consuming ATAQ’s electrolyte formula during your ride helps to replenish these electrolytes in the same ratio that you lose them (4:3:2:1) (2). As a bonus, the small amount of sugar in ATAQ’s formula will aid in the absorption of these electrolytes.
High intensity, short duration (<45 min)
Short (<45 min) and high intensity workouts are incredibly efficient. Interval workouts are a popular option for individuals short on time that want to maximize cardiovascular benefits. The high intensity (>80% VO2max) can be identified when riders are huffing and puffing, without the ability to chat with a riding partner. Assuming you are not riding on an empty stomach, you should be able to get through this short of a workout without any additional in-ride food. The caveat is if you are fasted (including an overnight fast) or on a ketogenic diet, then additional fuel might be needed to power those high intensity bursts throughout the workout. For these individuals, mouth rinsing is an often-overlooked option. Mouth rinsing is an option for individuals who may not have eaten in a while or feel they need a little extra kick to get through the workout. Recent research has shown that mouth rinsing for 5 to 10 seconds with a carbohydrate solution comprised of approximately 6% carbohydrates can improve performance in short duration (30-70 min) and high intensity (>80% VO2max) exercise. By rinsing, and not swallowing, the brain can recognize the carbohydrate solution and cue the central nervous system to improve performance before you spit out the solution. You’ve probably seen this tactic in play on the sidelines of pro soccer and football games. ATAQ’s watermelon electrolyte hydration drink mix combined with 5 oz of water is an easy (and tasty) way to consume the optimal 6% carbohydrate solution drink mix while simultaneously consuming electrolytes to aid in hydration.
The hydration goal is similar for almost all workouts, maintain hydration throughout the ride. An easy way to monitor fluid loss is with a scale. Simply weigh yourself before and after your workout (ideally without clothing so that sweat soaked kits don’t tip the scales). If you weigh the same pre and post workout then you have achieved the gold standard in hydration. However, this feat is very rare. Sipping an electrolytes beverage throughout the ride can help you maintain your fluid balance, especially for heavy sweaters. If you can lose less than 2% of your body weight in sweat then you are doing pretty well, but be sure to consume 16 to 24 oz of water after the ride for every pound you lost through sweat.
High intensity, medium duration (45-75 min)
Riders taking part in longer Peloton classes, Zwift races, or those overachievers that do two classes back-to-back, most likely fall into the high intensity, medium duration workout category. Since glycogen stores are depleted after approximately 90 minutes of high intensity exercise, medium duration rides will certainly tap into glycogen stores but will likely not deplete this fuel source. Thus, extra fuel is probably not required until after 75 min. However, if you are starting with low glycogen (which is the case for individuals who are fasted or on a low carbohydrate diet) then exogenous fuel might be required in order to maintain high intensity exercise. This fuel can be provided via mouth rinsing or ingesting small amounts of carbohydrates as tolerated at 15-20 min intervals throughout exercise. The preferred method of ingestion is in a liquid form due to its faster gastric emptying and in the form of glucose (30-60 g/h) with low fiber. Diluted orange juice or diluted Coca-Cola are easy ways to drink carbohydrates and provide a quick boost to your workout while also contributing to hydration. In addition, consuming some electrolytes during this time span could be beneficial for your performance, especially if you are a heavy sweater.
High intensity, long duration (90+ min)
Outside, a 90-minute ride is common. Indoors, however, 90-minute rides are rare. It could be due to the predominantly seated position, lack of terrain changes, or lack of scenery but rides over an hour and a half seem to test our attention span indoors. However, for those dedicated individuals that venture into the longer indoor rides and races, fueling plays a large part of your ride’s success. These longer rides will deplete glycogen stores and definitely require cyclists to take on exogenous fuel sources. Neglecting to eat during these rides can result in bonking. Even if you aren’t familiar with the term “bonking” you have likely experienced the phenomenon. Have you ever been cruising along, crushing the pace in a group ride or race then, all of a sudden, feel terrible? Suddenly, your great pace went to a screeching halt and it became a herculean effort to maintain a crawling pace. In cycling, we refer to this horrendous state as “bonking” or “hitting the wall”. Too many cyclists have a similar story to tell. “Hitting the wall” is a state in which your fuel reserves are depleted and you are unable to produce energy fast enough to maintain exercise intensity. Unfortunately, most cyclists are unaware that their fuel reserves are getting low until they have reached this rock-bottom. To avoid this state, aim to consume 30-60 grams of carbohydrate per hour. Preferably these carbs will come from glucose as opposed to fiber. If you prefer liquid carbohydrates then shoot for ingestion at 15-20 min intervals throughout exercise. If gels or solid food are your carbohydrate form of choice, then optimal consumption is every 20-40 minutes. There are plenty of liquid and gel sport products on the market that could provide the necessary carbohydrates for your ride, but be wary of consuming multiple gels in one workout as multiple gels are difficult for the gastrointestinal tract to handle. High carbohydrate solid food options include: bananas, oatmeal bars (that are low in fiber), grapes, watermelon, oranges, rice cakes, or a piece of toast,
As your ride extends in duration, hydration becomes even more pivotal. When working out for over 90 minutes electrolyte beverages become beneficial for everyone. If proper fluid balance is not maintained for these longer rides, it can become dangerous. Taking care to stay hydrated, have a fan on you while riding (if possible), and replenish electrolytes will help keep you riding strong throughout the entire workout.
What should I eat/drink AFTER?
The hour immediately after exercise is incredibly important to replenish fluids, protein and carbohydrates to start the recovery and muscle building processes. Consuming 20-25 grams of protein after the conclusion of your ride significantly increases muscle protein synthesis. If you are tight on time, or food, as little as 10 g of protein has been shown to have a mild effect on muscle growth. More details on the specifics of how, when, and why to take protein can be found in our previously published protein article “How much protein do I really need?”. Mixing your post-workout protein with carbohydrates will aid in muscle protein synthesis and glycogen replenishment. Optimally carbohydrates will be consumed in a 2:1 or 3:1 ratio to protein (3). So, if you consume 20-25 grams of protein post-ride, then aim for 40-75 grams of carbohydrates. This ratio can be attained with many protein powders and a high carbohydrate food such as cereal, bananas, blueberries, oats, sweet potatoes, lentils, or chickpeas. Other protein and carbohydrate combinations include: peanut butter and jelly sandwich, Greek yogurt with granola, or chocolate milk.
Hydrating after your ride is meant to replace the volume and structure of the fluids you lost through sweat. If you are unable to weigh yourself post-workout, you can monitor your hydration levels via your urine color. Dark yellow/brown urine is indicative of a severely dehydrated cyclist. Consume plenty of water and an electrolytes to rehydrate. Clear urine is the gold standard. If this is the case, continue to consume beverages to maintain your hydration level. As a note, when assessing urine color, be sure to monitor the color of the stream before it hits the toilet bowl/urinal. Once urine enters the toilet bowl, the color is diluted by the presence of a large volume of clear water already present in the toilet. If you are able to weigh yourself pre- and post-ride, aim to lose less than 2% of your body weight in sweat. For every pound lost through sweat consume 16 to 24 oz of water to rehydrate.
What should I take away from this article?
- Your time is important, so make the most of it by fueling appropriately
- Have a high carbohydrate snack of you are gearing up for a high intensity ride
- Drink 14-20 oz of water 2 hours before riding
- During the ride
- Duration and intensity of your ride will determine how much fuel is needed
- Low intensity rides should focus on hydration
- High intensity rides, especially those of medium and long duration will benefit from consuming carbohydrates throughout the workout (30-60 g/hour)
- Continue to stay hydrated with water and an electrolyte beverage (especially if the intensity if high)
- Consume 20-25 g of protein to jumpstart recovery and muscle protein synthesis
- Ingesting between a 2:1 and 3:1 ratio of carbohydrates: protein will aid in muscle repair and glycogen replenishment
- Monitor hydration status via a scale or urine color and consume 16-24 oz of water for every pound lost through sweat. Drink an electrolyte mix to speed up rehydration.