bike75.gif (2872 bytes)


  Latest update: 1/13/2024

Recovery and Fatigue Syndromes

Overtraining, Overreaching, and Chronic Fatigue

Recovery is essential to a successful training program. If you don't recover adequately, you won't get the maximal training benefit from the time on the bike, and increase the chance of increase sliding into an overtraining syndromes.

This is a nice summary of the essentials of a successful recovery strategy. Key points:


The increase in the level of performance of elite athletes along with a broader knowledge of optimal training regimens has dramatically influenced current training methods. A single training bout per day was previously considered sufficient, whereas today's athletes regularly train twice a day or more. Consequently, the number of athletes who are experiencing overtraining is increasing.

The goal of training is adaptation and improved performance which includes breakdown (training) followed by the recovery (rest). Overtraining is the result of an imbalance between training and recovery. It is assumed that the relationship between training and improved performance is an inverted U. There is an optimal amount of weekly training for any athlete. Do too little or too much and performance falls off.

Overreaching (short term overtraining) is thought to be the result of insufficient recovery in the muscle cell which translates into a decline in ATP levels. Overtraining is a more complicated physiologic problem, perhaps related to failure of the hypothalamus to cope with the total amount of physical stress.

In addition to the imbalance between training hours and rest time, is the question as to whether a rider's nutrition is adequate to replace the Calories consumed by their physical training program. This imbalance results in a condition that has been called RED-S (Relative Energy Deficiency in Sport).

This can be as simple as a "within-day" energy imbalance or deficiency as noted in this study which documented "..a significant correlation between the largest single-hour Calorie deficits and hormonal disturbances such as lower testosterone and higher cortisol"..which might impact performance.

Or, as suggested in this article an imbalance that develops over many days of riding as the result of under-eating relative to training demands.

Most regular cyclists have learned that it is not very hard to justify that extra serving at dinner after a day of riding, and then see the extra pounds slowing add up. The common response is keeping a close eye on the scale and the size of the servings on the plate, and tending to guess on the low side as to total caloric replacement needs. Guess wrong and the risks are not only long term physical problems such as osteoporosis or infertility, but the ore immediate issue of a pervasive lack of energy impacting daily training and riding - what may be the first step in the development of an overtraining syndrome which can often take weeks and months to resolve.

And as is pointed out, it is possible to experience RED-S without any loss of body weight. Maintaining an ideal weight is important to cycling at your best, so you don't want unbridled gluttony, but if you find you are tiring more easily than you have in the past, and are not reaching those training benchmarks, be sure to take a good look at your nutritional training program to be sure you have not underestimated your Caloric needs.


Fatigue is the tiredness you feel after a long or intense ride. Fatigue tells us we are pushing our physical limits and can be a warning that we are pushing too hard, that there may be an imbalance between exercise and recovery, and indicate the need to ease up or risk an actual deterioration in our performance. Thus the common dilemma in a personal training program: Hard work makes us faster, but how much is too much?

The 5 types of fatigue are:

  1. The bonk is the fatigue that accompanies muscle glycogen depletion and usually develops 1 to 2 hours into a ride. It is a particular problem if glucose supplements are not used on an extended ride.
  2. Post ride fatigue is a normal response to several hours of vigorous exercise and is expected when we are pushing our training limits, and should lead to improved performance over time.
  3. Overreaching is the fatigue felt at the end of a particularly hard week of riding and lasts from a few days to 2 weeks. It is associated with fatigue, reduction of maximum performance capacity, and a brief interval of decreased personal performance. It is a warning that we may be flirting with overtraining. Recovery is achieved with a reduction in training or a few extra days of rest.

  4. Overtraining (overtraining syndrome, staleness, systemic overtraining) is the result of many weeks of exceeding the athlete's physiologic limits and can result in weeks or months of diminished performance - symptoms normally resolve in 6-12 weeks but may continue much longer or recur if athletes return to hard training too soon. It involves mood disturbances, muscle soreness/stiffness, and changes in blood chemistry values, hormone levels, and nocturnal urinary catecholamine excretion.

    Stress factors such as the monotony of a training program and an acute increase in training program intensity lasting more than a few days increase the risk of development of overtraining. On the other hand, heavy training loads appear to be tolerated for extensive periods of time if athletes take a rest day every week, and alternate hard and easy days of training.

    For those of you interested in more on the the basic physiology of overtraining, this paper goes into more detail on the syndrome itself, and this one suggests diagnostic approaches.

    The underlying pathology is thought to be related to autonomic nervous system imbalance and/or a problem with the endocrine system. Several findings support this thesis. During heavy endurance training or overreaching periods, the majority of studies indicate a reduced adrenal responsiveness to ACTH which is compensated by an increased pituitary ACTH release. In early overtraining syndrome, despite increased pituitary ACTH release, adrenal responsiveness continues and serum cortisol levels fall. In advanced stages of overtraining, pituitary ACTH release falls as well. In this stage, there is additional evidence of decreased intrinsic sympathetic activity and sensitivity of target organs to catecholamines - indicated by decreased catecholamine excretion during night rest, decreased beta-adrenoreceptor density, decreased beta-adrenoreceptor-mediated responses, and increased resting and exercise induced plasma norepinephrine levels.

    The role of a decrease in the responsiveness of the ACTH - cortisol axis is supported by studies that show a decrease in post ride salivary cortisol levels (the level normally rises with the stress of exercise) in overtrained athletes.

    There can be a psychological toll from overtraining. For the most part, the competitive athlete is a well-adjusted individual who demonstrates less depression, anxiety, and fatigue than nonathletic counterparts. The well-trained athlete, however, may also have a personality that is somewhat rigid, strongly goal oriented, and perfectionist. It is not unrealistic to expect that when confronted with diminished performance or success, such an athlete may be compelled to drive himself or herself harder to succeed. This can express itself in the form of depression and accompanying chronic fatigue.

  5. Pathological fatigue is fatigue that cannot be explained by training volumes and is generally associated with medical conditions such as infection, neoplasia, disorders of the blood, cardiovascular, or endocrine systems, and psychologic/psychiatric disorders. Included in this grouping are the side effects of medications and "chronic fatigue syndrome" - an ill defined medical condition. A recent article has muddied the water even further by describing muscle changes from years of high volume exercise training that may be related to this entity. Another controversial possibility is iron deficiency without anemia - although this is much more common in endurance runners than cyclists.

Overreaching is common in all training programs and is a particular risk if the cyclist has made sudden or dramatic changes in:

Overreaching is common enough that a regular self assessment of the athlete's fatigue level should be part of all training programs. This is made more complicated when:

are part of the equation.

If overreaching is suspected, it is time for a break. Take a few days off the bike and if performance does not improve, it's may be time to take a longer break from riding, switching alternative aerobic activities to maintain aerobic fitness. Ignoring the signs risks slipping into overtraining territory and a month or two off the bike to recover.

It may the toughest part of your training, but adhering to a regular weekly rest schedule and heading back home if the legs are telling you it is not the day to push will minimize the risks of overreaching. Most trainers would include at least one and occasionally two days off the bike per weeks with an additional day of easy spinning.


Cyclists are one of the few groups of athletes capable of reaching the over trained level associated with prolonged fatigue. It has been speculated that this is due to the way cycling stresses the body with muscle activity concentrated in a single muscle group - the quadriceps. And it isn't necessary to undertake an extensive training program to be at risk. Even those working out sporadically (and with light training schedules) are at risk. While a professional cyclist might consider a 50 mile ride as part of a light recovery week, your 20 mile ride could produce all the symptoms of overtraining.


How do you know when you are in danger of OT? The following are clues which might suggest that an extra day or two of rest is in order.

But when it comes right down to it, you are how you feel, so to speak. Your sense of well being, sense of fatigue throughout the day, and sense of perceived effort as you take that weekly ride over your regular route all appear to be more sensitive than the most sophisticated laboratory study in identifying early overtraining.


Intervals are the best path to improving performance, but should you split your time between interval training and what we will call active recovery (riding at lower intensities)?

This article supports the idea that maximizing training requires the appropriate distribution of training time over several intensity zones. Researchers compared riders based on time spent in three zones:

Those who spent most of their training time in Zones 1 and 3 instead of Zone 2 enjoyed greater gains in their anaerobic power. This strategy of alternating between easy and very hard effort and avoiding the middle is known as polarized training.

Here is another well written article on balancing training intensity, and for those interested a link to the abstract of the original scientific paper. Although these are studies on running, the CV training benefits should be quite similar for cycling (or swimming).

As you develop a training plan, remember

  1. Focus your training time on both ends of the intensity scale, avoiding the middle. Adding additional long moderate miles won't provide a benefit equivalent to the time you are putting in.
  2. Don't short change the benefits of rest and easy riding. If you don't allow adequate recovery (riding at lower training intensities) you will not only fail to benefit from the extra riding time but may actually be sacrificing your performance.
What is a good intensity balance? Most authorities suggest 20% of your training TIME at a moderate to high intensity (a perceived effort of 6 - 10 or > 77% MHR) and 80% at a PE of 4 or less.

Now that you have the numbers, the challenge will be to keep those "slow and easy rides slow and easy. My guess is you will have to work to keep that HR down. Buried in the middle of this blog is a practical suggestion to apply the 80/20 approach to maximize improvement.

Although it is for running, the same approach of decreasing the emphasis on mileage with more focus on intensity can be applied to biking. To quote: "Don't calculate total miles per week in your diary (training log); that will encourage you to pile up junk miles and prevent you from learning how to run fast. .....Set up a program in which you

Finally, this blog from Road Bike Rider once again emphasizes the importance of balance in a training program.

HEART RATE VARIABILITY - a clue to early overtraining?

Heart Rate Variability (HRV) is a measure of the slight variation in timing between heartbeats. It is measured in milliseconds. HRV is influenced by the autonomic nervous system and is assumed to reflect the sympathetic-parasympathetic balance.

Normal values for HRV are an average of 100 msec in the first decade of life and decline by approximately 10 msec per decade lived. At age 30-40, the average is 70 msec; age 60-70, it's 40 msec; and at age 90-100, it's 10 msec.

This article includes an annecdotal report of a fall and then rapid rebound of HRV after COVID-19 and influenza vaccinations.

And an article in suggested it might be useful in a training program. "HRV can be very helpful in training because a higher HRV usually indicates good training readiness.....For example, if you notice your HRV is on the high end of your average, you might increase the intensity or duration of your upcoming workout. And on the flip side, if your number is dipping lower than usual not just one day but consistently, it could indicate that you've been pushing it too hard and need to dial things back. Although logic suggests HRV might play a useful role in identifying overtraining, closer study failed to show it supplied any helpful information. Below are 3 (of many).

Perhaps future modifications will improve its value, but for now there is too much day to day variability in the HRV data for it to be useful in identifying when you are pushing too hard and are at risk for overtraining.



So stick to a balanced approach. A training program structured to avoid too much intense exercise provides numerous health as well as performance benefits. Let your body tell you when it is time for an extra recovery day.


In a nutshell, overtraining is the result of "doing too much, too quickly". The body likes regular, moderate changes, not upheaval, in a training program. So don't increase your mileage or training time by more than 10% per week.

The most important step in preventing OT is realizing you are almost there. A good training diary is the single most important tool you have at your immediate disposal to alert you to the risk. In addition to the usual training facts such as mileage and times, it should include a daily notation on:

For professional coaches, there are some intriguing additional tools and literature available.


I think this article presents a balanced set of recommendations for most cyclists. (Unfortunately has blocked their articles but sometimes if you clear your cookies and refresh you can read one article before it figures out you are not a subscriber). Setting limits on the number of riding days (or hours) per week is a particular challenge for those who are competitive and eager to improve. The downside risk of too many miles and riding days is increasing the odds of overtraining and, paradoxically, losing ground on standard performance metrics such as FTP.

Following are my paraphrased excerpts from the article:

  1. Three Days a Week - the majority of avid cyclists

    The ideal for the majority of people. It's a feasible commitment for individuals with lives and careers outside of cycling, and there's still time for rest and strength training. And with three rides, there's an opportunity to vary and tailor your training to your goals.

  2. Four to Five Days a Week - competitive cyclists

    With four or five days a week, you're getting into the realm of competitive athletes. Four to five days per week is also a good sweet spot for athletes who are training for a longer event, especially if they don't have another form of aerobic conditioning.

  3. Six to Seven Days a Week - the professional athlete

    Those riding six to seven days a week are professional athletes. The demand and the stress that it puts on your body is pretty extreme. If you have a full-time job or are running around after children, you probably don’t have the time to cycle every day and properly recover, particularly if you're going long or hard on those rides. Six days allows one full day off a week to recover completely. It's not just a physical recovery but mental recovery to just kind of get away from the bike.`


Overtraining refers to prolonged fatigue and reduced performance despite increased training. Its roots include muscle damage, cytokine actions, the acute phase response, improper nutrition, mood disturbances, and diverse consequences of stress hormone responses. The clinical features are varied, non-specific, anecdotal and legion. No single test is diagnostic. The best treatment is prevention, which means

Overreaching is a normal part of the training/recovery cycle, but if your performance is not improving after a few days of recovery, it's time to switch to other aerobic activities which will keep you at 70% of your maximum heart rate (to maintain your level of fitness) or risk entering the zone of OT which may take a month or two to recover.

How long do you need to rest? If you have made a significant increase in your training schedule, and have been at it for 3 weeks or more, the chances are that you are entering that gray zone of overreaching. If so, recovery (and again this means keeping your general level of aerobic activity at 70% max. heart rate, not complete inactivity) takes at least 3 days and often up to several weeks as opposed to the normal recovery cycle of less than 3 days. The implication in that situation is that you may need more than 1 or 2 days of rest before a big event to perform at your personal best.

You can structure your training program to decrease the risk of overtraining. It should include at least one (and sometimes two) rest days per week as well as a day or two of easy spinning. This reflects the practical experience of coaches who have had to deal with the results of pushing too hard for too long. Increasing variation (decreasing monotony) both in your training routine from week to week (long rides, intervals) as well within individual rides has been proven to minimize training stress and decrease the risk of OT.

As in all aspects of personal training programs there is individual variability, so it is up to you to decide where to draw your own line. But remember that rest is a key part of any training program and may be the toughest training choice you'll have to make. And finally, don't forget to pay particular attention to post exercise carbohydrate replacement. Part of the fatigue of overtraining may be related to chronically inadequate muscle glycogen stores from poor post training ride dietary habits.


I ran across this personal story on and thought it might tie it all together for a few of you. To quote from that article:

"Question: I've been racing for four decades, averaging about 700 hours of training each year. But now I'm 59 and sometimes feel the motivation is just not there. I heard that a 67-year-old finished El Tour de Tucson (111 miles) in 4:51. He had significantly reduced his on-bike training to 4 days per week and lifts weights the other 3 days. Do you think I can cut back my training that way and still ride well? -- Bill S.

Coach Fred Replies: That's a great question, Bill. And because I'm 59 like you, I can provide an answer based on experience. Sometimes it's been bitter experience! I think that 700 hours of training a year may be excessive if two conditions are present:

But the real signal that you're doing too much is your level of enthusiasm. If you plan to race but then don't feel like doing it when the time comes, this conflict is a sure sign that you're overdoing it. The best indicator of long-term overtraining is loss of motivation.

In general, our ability to recover from exercise decreases as we age. But studies show that we can retain most of our aerobic power as long as our training is intense. In some cases, older cyclists who ride extremely well are doing more high-intensity workouts than they did in their 20s.That seems like a contradiction. How can we train intensely if we can't recover as well? But the answer is simple: Make more time for recovery between hard workouts. Hence the 4-days-per-week riding regimen of the Arizona roadie you mentioned.

Weight training is important, too. Past age 55 we encounter sarcopenia, a fancy name for loss of muscle volume. Resistance training helps us retain enough muscle to propel us down the road later in life.

If I were you, I'd hang up the bike for a while here in the off-season and concentrate on weight training and different aerobic activities like those mentioned above. Then when you begin riding again, limit the bike to 4 days per week. On 2 of those days, do hard work (intervals or hilly rides).Make the other 2 rides very easy. Lift 2 days per week. Take one day off to rest.

Try this schedule for 6 weeks and see what happens. I bet you'll be faster and more enthused. Keep it up and you'll ride great in road races, 40K time trials and fast centuries."

And a question I received earlier this winter:

Q. Hi, I'm a sixteen-year old cyclist who has been avidly into the sport for the past fifteen months. My interest in the sport has led me to buying books and searching the web for the best information to help me push myself just that bit faster.

In the last two or three months, my resting heart rate has been gradually getting higher and higher. I used to wake up in the morning to the sound of my heart beating around fifty times each minute, but now it seems to be up around seventy. In the time that it took for my heart rate to increase like this, I haven't noticed a large reduction in my riding capacity until now. I feel as though I have improved my fitness compared to when my heart rate was twenty beats lower, yet while on a social ride with the other members of the club today, I was going along alright until someone broke away. While the bunch chased, I couldn't maintain the high pace the other riders were producing. Cyclists who I was once much faster than had to go around me as my speed kept going lower and lower. I felt as though I just could not handle the high speed I previously thrived in.

Can you explain to me what I'm doing wrong? After witnessing what happened today, I think I am crossing from over-reaching into overtraining. I still have a huge interest in the sport and I have always kept control over my distances and intensity, always managing to have rest days after hard days. It puzzles me to see my performance drop like this - LS

A. It sure sounds as if you are working too hard at getting better. Interesting what the body can do to tell you to slow down. Since it is winter, you might consider backing way down for a couple of weeks - a little spinning. Half the miles, and a little alternative work on the cross country skis. Then when you start up again, hold it to 5 days max on the bike and a couple of them long slow distance.

All questions and suggestions are appreciated and will be answered.

Cycling Performance Tips
Home | Table of Contents