Should I be eating protein when racing long? What are the pros and cons? – Ferno G.
Milo of Croton was an Olympic wrestler born in the 6th century BC (no prizes for guessing where). Standing nearly 7 feet tall, he was a giant of the ancient Olympics. Legend has it that he drank ox blood for fuel and ate raw animal flesh. The idea that protein was the most essential nutrient for sporting success lasted until the late 1960s. Then, a team of Scandinavian researchers established the link between carbohydrate consumption and delayed glycogen depletion and everything changed (1). We now prioritize carbohydrates above all else, almost to a fault.
In running races, people have developed an aversion to protein, stoked partly by fear of gastrointestinal (GI) upset (already a considerable problem in ultrarunning) and partly by our over-dependence on the media for sports nutrition advice. Society is obsessed with high vs. low-carb diets and deriving the optimal dose, formulation and timing of the latest energy supplements. Rarely does protein feature in a conversation dominated by sports drinks, gels, hydrogels, jellies and candies. Could this be a mistake?
Most of us know that dietary protein is critical for repairing muscles that are damaged by training and racing. High-level athletes wouldn’t go a full day, or even a meal, without a decent protein feed. Yet many of those same individuals readily forgo protein when it comes to race day – arguably at a time when they need it most.
Muscle protein is in a constant state of flux, perpetually being broken down and repaired. A long race, or one with considerable ascent and descent, could double the rate of muscle protein breakdown, driving up the need for dietary protein to compensate. We can estimate muscle damage by measuring an enzyme, creatine kinase (CK), in the blood, seeing values of approximately 150 U/L at rest, up to 1000 U/L after a marathon, but more than 10,000 U/L after a long ultramarathon (2). This extreme muscle stress causes pain and inflammation (you know what I’m talking about). It's arguably the main impediment to performance in long races, lingering for days or weeks after crossing the line. But why wait until the race is done to address this profound problem?
Consider experimenting with protein intake during longer runs, say more than 12 hours. You can try small quantities at first, no more than approximately 10 g every few hours, and only in an event where you can afford to experiment with your nutrition strategy (i.e., not an important race). Then, modify your approach based on individual tolerances. Take advantage of the inevitable shift in food cravings (from sweet to savory) that tend to occur after many hours of running: savory snacks usually contain more protein.
Is there a particular training run that can be used as a predictive gauge for how well the athlete will perform in the event? –@mike.5kgeezer
The best way to gauge your “readiness” for an event is to do a challenging run on the terrain and environment you’ll encounter come race day. That means designing something bespoke for each race. Most big races – UTMB and Western States come to mind – have dedicated training events that allow runners to recon the course under controlled conditions, but nothing is stopping you from exploring the course yourself and testing your legs.
If you want something more broadly applicable, professor Gui Millet (University of Saint-Etienne) and I recently proposed a treadmill-based protocol to assess a runner’s tolerance to ultramarathon-specific physiological stress (2). As alluded to in the previous response, muscle damage and associated fatigue are among the most prominent performance limiters for most people, especially in long races (e.g., more than 100k). And, unlike gastrointestinal distress, which is another major factor inhibiting performance, muscle damage cannot be reversed in-task through changes in pacing or nutrition or with medication. Once microtrauma and inflammation occur in the muscle, you’re stuck with it until you rest and recover, which could take days.
Rather than running 100 miles to evoke muscle damage, we proposed a downhill running protocol, which causes muscle damage and fatigue due to long muscle lengths and braking forces, making it distinct from the damage following resistance exercise (4). Ideally, the downhill protocol would mimic the descents typical of major mountain races – for instance, 5k of downhill running, comprising of 2,300-3,300 feet of negative elevation, equating to a slope of approximately –15%. The speed is not as important as the gradient – use a speed that reflects your ability. In our protocol, we suggested measuring muscle contractile function and blood biomarkers of muscle damage. However, you can instead log your perceptions of effort and the severity of muscle soreness and see how both change over time to gauge your competitive readiness.
Note that even ultramarathons considered relatively “flat” still have substantial ascent and descent owing to the extreme distances (e.g., the Javelina Jundred, a race run on hard-packed granite, rocks and sand comprises 7,900 feet of total ascent and Badwater 135, a race contested almost entirely on asphalt, involves approximately 14,760 feet of ascent and 6,560 feet of descent). Accordingly, wherever possible, one should design a training run that resembles the demands of the target event.
Do you have to progress to run an ultra, like starting at a 5k, 10k, half (marathon), full (marathon) and so on? Road running is so boring and ultras all seem to be through scenic areas. –@timkilgore
Physically, starting small and progressing your mileage allows you to apply the principle of progressive overload: slow but continuous increases in stress that improve endurance.
I ran over two dozen big city marathons and half marathons before I got into ultra and trail running, and I must confess, I have fond memories of just two of them. Most of the time, I dodged crowds, hurdled discarded water bottles and looked at the backs of runners’ heads while prominent city landmarks passed by in the periphery. (My first half marathon comprised three loops of a deserted F1 racetrack). Some people thrive in those environments, but I’m not one of them. Enduring these races isn’t a prerequisite to ultrarunning. You don’t need to pay your dues, and we all know people who began their running journey with a trail marathon and progressed from there. That said, the foundation those road races gave me, both in body and brain, was valuable in smoothing my transition to the trail. There are several reasons to take the stepwise approach you mentioned.
Physically, starting small and progressing your mileage allows you to apply the principle of progressive overload: slow but continuous increases in stress that improve endurance. The cardiovascular and musculoskeletal systems adapt over time without sudden, disjointed leaps in mileage that markedly increase your injury risk.
Psychologically, taking the leap from a standard marathon to an ultramarathon is a tough pill to swallow. Marathons are normalized and ubiquitous in modern culture. We’ve all run one or know somebody who has, but to run 26.2 miles (42.2k) only to be hit with the realization that you’re one-half or one-quarter of the way through the race is stressful and disheartening. I’ve previously described this psychological barrier as the shifting threshold. We generally agree that ultramarathons, especially long ones, hinge more on psychological toughness and resilience than physical prowess, but, just like muscle strength, mental toughness takes time to develop.
Lastly, applying a steady increase in race mileage is supported by at least two psychological models: self-efficacy theory, which states that an individual's belief in their ability to succeed influences motivation, behavior and performance, and goal-setting theory, which states that motivation and performance benefit from targeted goals (those that follow the “SMART” principle: specific, measurable, achievable, realistic and time-dependent).
Of course, it’s all a misnomer because trail races don’t start at “ultra” but range in distance. Look hard enough, and you’ll find trail races from 5k to 500k, with enough options to ensure you’ll get the scenery and mileage you desire without being forced into loop after soul-sucking loop of deserted tarmac.
References
1. Bergström J, Hermansen L, Hultman E, Saltin B. Diet, muscle glycogen and physical performance. Acta Physiol Scand 71: 140–150, 1967. doi: 10.1111/j.1748-1716.1967.tb03720.x.
2. Tiller NB, Millet GY. Decoding Ultramarathon: Muscle Damage as the Main Impediment to Performance.
3. Babcock MC, El-Kurd OB, Bagley JR, Linder BA, Stute NL, Jeong S, Vondrasek JD, Watso JC, Robinson AT, Grosicki GJ. Acute Cardiovascular Responses to the 100-Mile Western States Endurance Run.
4. Bontemps B, Vercruyssen F, Gruet M, Louis J. Downhill Running: What Are The Effects and How Can We Adapt? A Narrative Review. Sports Med Auckl NZ 50: 2083–2110, 2020. doi: 10.1007/s40279-020-01355-z.