Marathon training is like preparing for a boxing title match: months of lonely workouts culminating in one exhausting battle.
In contrast, if you’re in the midst of a season of 5k, 10k, and half marathon races, there’s no definitive end-point, no end-all be-all day that defines your season. This can make it tough to pull the plug—especially in the spring and summer, there’s always one more race that you want to run.
If you can just keep up your fitness for a week or two, you think you might have another crack at a PR. Before you know it, you’ve been racing for weeks on end, and you’re feeling a bit burned out.
When it’s time to hit the reset button after a season of short and medium-length road races, how much time off do you need? Answering that question is a going to be a matter of weighing the amount of physical and mental recovery you need against the potential downsides of losing fitness during your time off and having a harder time working back to training.
Though a 5k, 10k, or half marathon won’t beat you up as badly as a full marathon or an ultra, you’ll still accumulate fatigue and muscle damage as you continue to race often.
For example, a 2002 study by researchers at the University of Connecticut found that racing a 10k reduces your muscular strength and especially explosive power for at least 48 hours post-race.1
With regards to the half marathon, two studies by a research team in Italy found that that biological markers of muscle and liver damage are elevated in half marathon finishers for at least 24 hours following the race.2, 3
Unfortunately, neither of these studies followed up two, three, or four days later, so it’s hard to say when these levels returned to normal. However, another study by Lance Dawson, Kimberly Dawson, and Peter Tiidus at Wilfrid Laurier University in Canada found that it took four days for muscle soreness to completely return to baseline values following a half marathon.4
Another equally important consideration is recovering from mental stress.
Running a great 5k, 10k, or half marathon takes a tremendous amount of mental effort. Mental exertion has finite limits, just like physical exertion.
Research on the phenomenon of “ego depletion” shows that completing a task that requires a lot of focus or concentration, like running an all-out race, will reduce your ability to perform well at subsequent tasks, whether they’re physiologically related or not.5 There’s no research on how long it takes to recoup your mental energies (and it probably varies from person to person), but the time you need for mental recovery is likely proportional to how much mental energy you’ve expended during your racing season.
If you’ve had a lot of long, tough, grueling races, you’ll probably need more time off than if you’d only done a few low-key races. The Italian coach Renato Canova, who works with many of the best Kenyan and Ethiopian distance runners, writes that top marathoners often need two months of mental relaxation and low-key training before they’re able to turn their full attention back to preparing for another marathon.
You probably won’t need that long, but the lesson remains: don’t neglect mental recovery!
While time off from running is great for physical and mental recovery, it can pose some risks, too.
If you take too much time off, you’ll lose a good chunk of the fitness you worked so hard to acquire, and it can be harder to avoid injury when you’re working back into training. According to Jack Daniels, you’ll lose no fitness from your first five days off from running, but after two weeks of total rest, you’ll have lost about 3% of your initial fitness—30-40 seconds over a 5k.6
All the adaptations that allow you to run faster and further as you gradually increase your training also work in reverse when you take a lot of time off.
Ultimately, the perfect amount of time off will be something that varies from person to person, but by taking into account research on physical fatigue and intuition on mental fatigue, a good benchmark might be five to seven days of complete rest, and another week of short, easy jogs every other day to maintain fitness and mechanical integrity while still allowing you to refresh your mind and body. After that, you should be rejuvenated and ready to start up training for another season of racing.
References
- Gomez, A. L.; Radzwich, R. J.; Denegar, C. R.; Volek, J. S.; Rubin, M. R.; Bush, J. A.; Doan, B. K.; Wickham, R. B.; Mazzetti, S. A.; Newton, R. U., The effects of a 10-kilometer run on muscle strength and power. The Journal of Strength & Conditioning Research 2002, 16 (2), 184-191.
- Lippi, G.; Schena, F.; Montagnana, M.; Salvagno, G. L.; Banfi, G.; Guidi, G. C., Significant variation of traditional markers of liver injury after a half-marathon run. European journal of internal medicine 2011, 22 (5), e36-e38.
- Lippi, G.; Schena, F.; Salvagno, G.; Montagnana, M.; Gelati, M.; Tarperi, C.; Banfi, G.; Guidi, G., Acute variation of biochemical markers of muscle damage following a 21‐km, half‐marathon run. Scandinavian journal of clinical and laboratory investigation 2008, 68 (7), 667-672.
- Dawson, L. G.; Dawson, K. A.; Tiidus, P. M., Evaluating the influence of massage on leg strength, swelling, and pain following a half-marathon. Journal of Sports Science & Medicine 2004, 3 (YISI 1), 37.
- Dorris, D. C.; Power, D. A.; Kenefick, E., Investigating the effects of ego depletion on physical exercise routines of athletes. Psychology of Sport and Exercise 2012, 13 (2), 118-125.
- Daniels, J., Daniels’ Running Formula. 2 ed.; Human Kinetics: 2005.
