As you age, inevitably you’ll tire sooner. You can’t ride as far so you quit sooner. You don’t climb as well. You can’t go as fast. You may not notice this yet — but it will happen. Through proper exercise you can slow the rate of decline — but eventually you’ll fatigue sooner. Fortunately by understanding fatigue you can mitigate it’s effects.
What Causes Fatigue?
Physiologists have multiple theories about what causes fatigue in endurance athletes. In How Badly Do You Want It Matt Fitzgerald explores why we get fatigued and don’t go longer or harder:
Muscular fatigue is caused by energy depletion. Riding you burn a mix of fat and glucose. Even if you’re skinny you have enough body fat for a ride. Your body stores glucose as glycogen and your glycogen stores are limited. When you run out of glycogen you bonk. And the remedy is simple – eat carbs. For more information see my columns:
- Anti-Aging: Preventing Bonking and Hitting the Wall
- Anti-Aging: Preventing Bonking with Daily Nutrition
Except in serious cases the dehydration itself doesn’t cause fatigue. The sensation of thirst does. You feel thirsty, you correctly interpret this feeling as starting to get tired. You think dehydration slows you down … so you slow down. It’s your interpretation, not the dehydration that causes you to feel fatigued. And the remedy is simple – drink. For more information see my columns
3. Inadequate oxygen.
Your heart is a muscle and it fatigues like your other muscles. As it fatigues less blood is pumped per stroke and your heart has to beat faster to deliver the same amount of oxygen and nutrients to your muscles. This is called cardiac drift. At some point your heart can’t beat any faster so the supply of oxygen to your muscles is can’t keep up. The remedy is to tell yourself “Ahh … it’s just cardiac drift.” And accept you will slow down.
4. Central governor.
This theory changes the cause of fatigue from physiological to mental. You have a subconscious system in your brain (central governor) that regulates how hard your muscles work so your speed / power never exceeds the capacity of your body to deal with the stress of exercise. However, no empirical evidence supports this theory.
Your conscious brain makes decisions about how fast or how long to ride based on your perception of how fast you are breathing and how hard your muscles are working, i.e., perceived exertion. When your perceived exertion exceeds what you think you can handle you slow down or even quit … even though it’s your mind telling you that you’re fatigued although your body hasn’t reached its limit.
Perceived Exertion is the Governor on How Hard You Can Ride
In How Badly Do You Want It Matt Fitzgerald uses a number of excellent examples of endurance athletes and concludes the limit is perceived exertion. If you perceive you’re going as long or hard as you can then you can’t do more. The book talks about various ways RPE can be changed.
Perceived exertion has two layers. The first layer is how your muscles feel. The second layer is how you feel about how you feel. Your perception and assessment are largely based on your prior experience. Psychologists call this anticipatory regulation. Based on past rides you anticipate how far / fast you can go.
Fitzgerald provides examples of how changing perception results in higher performance. I’ve added my own examples. if your perception of effort changes, you can do more.
Jonas Vingegaard won the 2022 Tour de France because he had the strongest team. His teammates paced him up the climbs with Sepp Kuss taking the final leg. Kuss knew he could ride harder because he didn’t have to maintain the pace to the finish. Vingegaard ignored his legs and breathing and just focused on staying with Kuss. Psychologists call this the group effect even if the group is just you and your buddy. Nations that dominate a particular sport are another example of the group effect. They produce more athletes. When an athlete competes, he knows his whole country is rooting for him. On a group ride you often do more than on a solo ride.
When a rider dons the maillot jeune in the Tour de France he feels stronger and rides better. In stage five of the 2004 Tour Voeckler was in a five-man breakaway that built up a 16-minute lead and finished 12:36 ahead of the peloton. Voeckler is French and overnight he became the hero of the French. In stage 10 the race entered the mountains and Voeckler was still in yellow. Day after day Voeckler rode beyond himself losing time every day but staying in yellow through stage 16. He rode beyond himself because of energy from the crowds, the audience effect. The advantage in team sports is another example of the audience effect. In an organized event volunteers at aid stations – your audience – cheer you on.
In the 2011 Tour de France Voeckler surprised everyone but himself by taking the yellow jersey. Again he held onto it much longer than anyone else expected. Based on his 2004 Tour, in 2011 Voeckler knew he could take the yellow jersey and defend it, the success effect. From group rides even if you’re drafting, you learn you can do more than you thought.
Marginal improvement effect.
The penultimate stage of the 1989 Tour de France was a 24.5 km time trial. Greg LeMond was 50 seconds behind Laurent Fignon. In order to win the Tour he had to ride 51 seconds faster than Fignon. Because Fignon started behind him, LeMond couldn’t pace himself based on Fignon’s performance. His plan was simple: to ride just a little faster with a little less in reserve than he’d ever ridden before – marginal improvement. LeMond won by eight seconds. You may not be able to ride two miles an hour faster but you probably can ride a little faster.
This season your long ride has been 55 miles. If your goal is to ride farther, you may start thinking about how you felt at the end of 55 miles and your other previous long rides. Pushing yourself past that level of fatigue is daunting, perhaps impossible. However, research shows if you have a quantitative goal, e.g., riding 100K (62 miles), you are more likely to be successful. You look forward in time and focus on your goal of riding 11 more miles; you don’t reflect on how you felt on other long rides.
In 2014 Bradley Wiggins rode 54.526 km (33.294 mi.) in an hour to break Alex Dowsett’s record of 52.937 km (32.894 mi). Wiggins thought it almost impossible to average 53 km/h (32.311 mph), which would break the record. However, he knew he could ride about 54 km/h for just 12 minutes. During the record attempt he focused only on each 12-minute segment. You may get tired on a ride and think you can’t finish the ride. Just focus on a small goal such as on climbing the next hill or riding to the next minimart, etc.
In my ultra-racing days I used a time trial on the CompuTrainer to establish my training zones by heart rate. Then I repeated the TTs to gauge my improvement. This was before power meters on bikes. However, during my TTs the CompuTrainer measured power. If I focused on my breathing, relaxing my upper body and not thinking about the TT and my power, I produced up to 5% more power for the TT!
Self-consciousness affects perceived effort. If you focus externally on the task at hand instead of how you feel you can go farther / harder.
Many champions think they perform better because they are used to suffering. Repeated failure is frustrating and a rider feels either defeated or angry. The anger can become a motivator to go a little harder. The suffering doesn’t have to be athletic. Frank Shorter who won the 1972 Olympic marathon was abused by his father.
Research substantiates these effects are real and change an athlete’s perceived exertion. (How Badly Do You Want It?)
Reread the above ways to change your perceptions of fatigue. How can you incorporate them? By using several of the above methods RBR reader Eli improved his climbing as described in this column Anti-Aging: How Can an 83-Year-Old Climb Long Hills?.
- Anti-Aging: 8 Tips to Cycling Smarter
- Anti-Aging: Riding Smarter As You Age Part 1
- Anti-Aging: Riding Smarter as You Age part 2
- Anti-Aging: How to Get and Stay Motivated
My eBook Gaining a Mental Edge: Using Sports Psychology to Improve Your Cycling is the primer I use with my clients. It’s divided into six chapters of progressive lessons on relaxation, focus, using powerful thoughts and images, building confidence and managing anxiety, creating a plan and visualizing it, riding the ride and dealing pain during the ride. Gaining a Mental Edge: Using Sports Psychology to Improve Your Cycling is only $4.99.
My eBook Anti-Aging: 12 Ways You Can Slow the Aging Process has individual chapters on each of the types of exercise the American College of Sports Medicine recommends: cardiovascular both endurance and intensity; upper, lower, and core strength; weight-bearing, flexibility and balance. I include interviews with Gabe Mirkin (recommendations from an M.D.) Jim Langley (importance of goals), Andy Pruitt (importance of working on your skeleton, posture, balance, muscle mass), Muffy Ritz (recommended activities for older people, especially women), Malcolm Fraser (recommendations from an M.D.), Fred Matheny (importance of strength training), Elizabeth Wicks (motivation) and five other male and female riders ages 55 to 83. Anti-Aging: 12 Ways You Can Slow the Aging Process incorporates the latest research and most of it is new material not published in my previous eArticles on cycling past 50, 60 and beyond. It’s your comprehensive guide to continuing to ride well into your 80s and even your 90s. The 106-page eBook Anti-Aging: 12 Ways You Can Slow the Aging Process is available for $14.99.
Coach John Hughes earned coaching certifications from USA Cycling and the National Strength and Conditioning Association. John’s cycling career includes course records in the Boston-Montreal-Boston 1200-km randonnée and the Furnace Creek 508, a Race Across AMerica (RAAM) qualifier. He has ridden solo RAAM twice and is a 5-time finisher of the 1200-km Paris-Brest-Paris. He has written over 40 eBooks and eArticles on cycling training and nutrition, available in RBR’s eBookstore at Coach John Hughes. Click to read John’s full bio.