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January 28, 2011
 
WHY THE FASTEST RUNNERS OFTEN GET STIFFED

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TRADITIONALLY, ENDURANCE ATHLETES have not placed a major emphasis on explosive strength training. The rationale for this avoidance of explosive work has been that such training might carry a high risk of injury, and that high-speed, “anaerobic” movements have little relevance for the “aerobic” athlete whose success depends on steady endurance.


However, scientific evidence continues to show that such thinking is wrong: The research reveals that explosive training helps endurance athletes in a number of key ways. For example, in a brand-new study carried out by Rob Spurrs and co-investigators at the University of Technology in Sydney, Australia, explosive training improved performance times for 3-K runners by almost 3%.


The explosive workouts designed by Spurrs and colleagues were simple to carry out, and the athletes performed them only two times a week for three weeks and then three times a week for three weeks (1). Just eight different, easy to-learn exercises were utilized (squat jumps, split-scissor jumps, double-leg bounds, alternate-leg bounds, single-leg forward hops, depth jumps, double-leg hurdle jumps, and single-leg hurdle hops), and the Australian athletes usually performed no more than four of these exercises per workout (generally using two to three sets of 10 to 15 reps per exercise). Before the six-week study began, the athletes were running about 35 to 50 miles per week.


Here are descriptions of the less-familiar exercises: To carry out split-scissor jumps, an athlete would start with one leg out in front of the other. If the left leg was in front of the right leg, the distance between the back of the left heel and the toes of the right foot would be approximately one shoe length. The athlete would then bend at the hips, knees, and ankles and then attempt to jump as high as possible. While airborne, his legs would cross so that the right leg would be in front of the left upon landing.


This action would continue for the duration of the set, creating a scissor-like action throughout the drill (and a split stance with each landing). Subjects were given instructions to jump as high as they possibly could – but with minimal ground-contact time during each landing stage of the movement.


Thus, the runners had to compromise the vertical height of their jumping somewhat in order to decrease the duration of ground contact. No restrictions were given to the athletes regarding the depth of knee or hip flexion, but the runners were asked to maintain upright posture with their torsos.


To perform depth jumps, an athlete stood on a box with a height of 40 centimeters (15.75 inches). Then, the athlete was instructed to simply step off the box, as though he were taking a routine step on normal ground. During the 40-centimeter, downward “flight,” the athlete had to quickly bring the non-stepping foot into position so that the landing was made on both feet simultaneously. Upon landing, the athlete attempted to minimize ground contact time and yet jump as high as possible. After coming back to terra firma following the explosive jump, the athlete simply stepped back onto the box and repeated the overall action for the prescribed number of times.


When stepping off the box, an athlete was not permitted to “step down” from the box, as he would when debarking from a train or stepping off a kitchen stool. Rather, the action was supposed to be a step forward from the box, as though another box of the same height was ready to meet the stepping foot – and then a quick 40-centimeter plunge. To carry out double-leg hurdle hops, an athlete jumped over 10 hurdles, positioned 115 centimeters (45 inches) apart, with a height of 70 centimeters (27.6 inches). The athlete jumped over each hurdle, landing and taking off on two legs, until all 10 hurdles had been cleared (movement was continuous). Again, the athlete was instructed to minimize ground-contact time.
While doing single-leg hurdle hops on one leg at a time, an athlete also jumped over 10 hurdles in continuous fashion, but this time the hurdles were only 42 centimeters (16.5 inches) high and were placed 160 centimeters (63 inches) apart. Minimal ground-contact time was again the order of the day.


The pervading theme for all of the exercises used in the investigation was to get as high as possible with the least amount of ground-contact time. For the double- and alternate-leg bounds and also for the single-leg forward hop (i.e., the drills which focused more intently on horizontal movements), this theme was also applied – but with the added instruction that the greatest-possible horizontal distance should be covered with the most-abbreviated-possible ground contact.


After just six weeks of the power sessions (15 workouts in all), the explosively trained Australian runners improved 3-K running time by 16 seconds, while control competitors (who ran in a similar way but did no explosive work) failed to upgrade 3-K running ability at all.


Interestingly enough, the explosive training also improved the efficiency of the Australian harriers, enhancing running economy (the oxygen cost of running at a particular speed) by from 4 to 7% at three different velocities. The training improved the rate of force production in the athletes’ calf muscles and also made the runners’ legs stiffer by 11 to 15%. Stiffer? Yes, I know that sounds strange. After all, isn’t stiffness supposed to be a bad thing for endurance runners, something you attempt to avoid by faithfully carrying out stretching activities?


Well, stiffness can be a negative, if it is excessive, but in this case the increased stiffness helped the runners react with the ground more explosively with each foot strike. Their legs were less compliant, and as a result they probably spent less time in the stance phase of the gait cycle without sacrificing an inch of stride length; in fact, it is likely that stride length was greater than before the explosive training began.


Overall, explosive training improves endurance-runners’ performances by expanding forward propulsion with each foot strike at an energy cost which is less than before and with a total foot strike time which is less than before the training began. Explosive training makes runners both more economical and faster.


What about injury? The power-trained Aussies suffered from nothing more than a little soreness after their first few explosive workouts; after that, everything proceeded smoothly. In fact, carefully conducted explosive training should be anti-injury, since it enhances muscles’ abilities to withstand high, sudden force loads. Overall, it is clear that explosive work is an essential part of an endurance athlete’s training. Endurance athletes who avoid explosive sessions have a difficult time achieving their highest-possible levels of performance. Buy The Book

 
January 16, 2011
 
Rest And Recover

Programming rest and recovery into your training schedules ensures important benefits.  First, you’ll be healthier—which means you’ll have minimal interruptions to your training from illness or injury, thus your training will be more consistent.  Second, by adequately recovering from the stress of training, your body’s musculo-skeletal and cardio-respiratory systems will adapt faster making you stronger and aerobically more fit.  In fact, Pfitzinger (2005) claims that, “It can be argued that your improvement as a highly motivated runner is chiefly limited by your ability to recover” (P.203).  I couldn’t agree more!  So the principle is simple:  train hard, then rest to recover.


Key to training and improving your performance is to stress, or overload, the body with a hard workout, and then to allow it to recover while it adapts.  Sometimes we refer to the recovery and adaptation processes as super-compensation.  These days, it is clear that overload (a well-known training principle – see Box 1) and recovery are the magic ingredients of any training program.  If I can get esoteric for a minute, overload and recovery are the yin and yang, representing balance in training.


Box 1.  The Principles of Progressive Overload


To improve, the runner must progressively overload his system with more frequency, or intensity, or duration of his training efforts.  This overload must be enough to cause new adaptations to the body.  Overload by itself is not sufficient to cause improvement.  It must be accompanied by recovery to permit adaptation to take place.


But as with many aspects of distance running, the devil’s in the details.  Many questions come to mind about the practicalities of implementing a successful recovery strategy into your program.  For example:


1. How hard should you work out to improve?
2. How many days should you train hard each week?
3. How much rest do you need to recover from a hard workout?
4. Should you have complete rest during your recovery days, or can you do other activities to maintain your cardiovascular fitness, while giving your legs a chance to recover from the pounding?


In this article, we’ll look at what conventional wisdom says about these questions concerning the non-nutritional aspects of recovery, and next month we’ll examine nutritional strategies for proper recovery.


When considering the factors that constitute proper recovery, we should first examine the myriad of lifestyle factors that affect our ability to recover from running.  The good news is that most of our lifestyle factors are controllable.  We can evaluate our lifestyle habits and then take measures to improve them. 


Here are some of the most common lifestyle factors that we believe contribute to maximal recovery.


Are You Quick To Recover Or Slow To Recover?


Alas, we have to take the cards that our genetic fate has dealt us, and make the best of it.  Our genetics are a major player in our ability to recover from hard workouts.  Some runners are flattened for days after a hard interval-training workout, while are able to run a solid ten miles the following day without the slightest ache or pain.  If you consistently recover from your workouts within 24-48 hours, count your genetic blessings!  If, like me, you hobble around for days after an intense workout, you’re going to have to live with the fact that you’re slow to recover and need to plan for a longer recovery, i.e., allow 2-3 days of easy running, or (gasp) actually take a day off completely from running.


How Does Age Affects Recovery?


Any master athlete will tell you that as we age we need more recovery time.  Over the age 40, we need anywhere from 1-3 days of rest and/or recovery workouts after a strenuous running session.  I leave this up to the reader to decide when to schedule a rest day and when to do light running workouts to ensure good recovery.  However, it should be noted that cross training is invaluable here, as it permits the runner to do a solid cardiovascular workout while giving legs a break from the pounding.  Thus the runner can train most, if not all, days of the week without interruption.  Moreover, cross training can be combined with strength training, something that most runners are notably remiss at doing.  Strength training has great benefits to runners in terms of strengthening muscle, tendon, and ligament, and improving lactate tolerance.  Lastly, older runners should be moderating their running sessions, supplementing or substituting their recovery sessions with cross training activities, and allowing more days between stressful running workouts to recover completely.


What About Gender and Recovery?


Women tend to take longer to recover from high stress workouts than men, largely because of hormonal differences.  Testosterone, the dominant male sex hormone, plays a big role in muscle growth and repair, conferring an advantage to males.  Although female athletes appear to have higher levels of testosterone than non-athletes, female athletes still have lower overall levels than their male counterparts and should avoid following training schedules that are designed for men.  There are also significant strength differences between the two genders due to size differences.  However, pound for pound, this difference is largely reduced as to make it almost insignificant.  But, women are likely to take longer to recover from running workouts because of the reduced overall strength.


What Is The Relationship Between Sleep and Recovery?


Quality and quantity of sleep significantly contribute to recovery.  Good sleep is essential for your body to repair itself, and conversely, a chronic (long term) inadequate volume and quality of sleep will impair your recovery from training.  Unfortunately, this essential requirement for recovery is grossly inadequate in most runners, indeed in most people.  Chronic sleep loss and poor quality sleep are endemic in the more developed western countries like the U.S.A, Canada, U.K., New Zealand and Australia.


Box 2.  How Does Sleep Repair The Body?


We sleep in 4 stages, alternating between non-rapid eye movement (NREM) and rapid eye movement (REM).  Each sleep cycle takes about 90 minutes.  The average adult sleeps about 7.5 hours, or five full cycles, with 20% of that time in REM.  Anabolism (repair) takes place during the four stages of sleep shown below, but particularly in stages 3 and 4.
Sleep deprivation is categorized as short-term and long-term.  A shortage of sleep will not cause a decline in running performance.  So if you are traveling internationally to compete in a marathon, and are short a few hours sleep, your performance should not be reduced, although sleep-deprived endurance athletes often complain that subjectively, their races feel much harder than usual (Bond et. al. 1986, also see October 2009 issue of Running Research News (volume 25 issue 8) “Coping With Jet Lag In International Marathons”. 


Researchers of short-term sleep deprivation have looked at its effects on VO2 max, treadmill running and walking to exhaustion, respiration levels, maximal heart rate, and other parameters of endurance exercise.  Generally, the data shows that sleep loss ranging from 4-60 hours does not impair performance in unskilled endurance activities like running, rowing, and swimming (Pilcher et al. 1996, Van Helder et al. 1989).  The adrenalin rush of competition appears to override any negative physical consequences of short-term sleep deprivation.  However, there is considerable variability in our response to short-term sleep deprivation. 


Some people are highly susceptible to sleep loss, while others seem to be resistant to it.  A study by Martin et al. (1981) highlighted this when they walked sleep-deprived subjects to exhaustion on a treadmill at a set pace.  Two sleep-deprived subjects actually increased their walking time to exhaustion, 4 showed no significant change, and 4 subjects showed a large decline in time to exhaustion!  This is something you need to bear in mind if you anticipate running with little or no sleep.  If you’re susceptible to sleep loss, expect to perform below your best.  In contrast, long-term sleep deprivation has been shown to reduce cardiovascular performance by 11% (Walters 2002) and slow glucose metabolism by 30%- 40% (Spiegel 1999).  So the implication here is that we should ensure that we get 7.5 to 8 hours of quality sleep every night for healthy regeneration. 


Some other quick advice:  eat your final meal of the day well before you go to sleep, and going to bed at the same time each night will set your circadian rhythms into a nice routine.   Also, avoid bright lights at night, and if you’re not sleeping well, examine your life stressors and whether you are overtraining.


The good news about sleep and training is that scientists have shown that people who exercise regularly and intensely (without overtraining) spend more time in stage 3 and 4 slow-wave sleep.  For example, Trinder et al. (1985) found that fit runners, who average 45 miles/week, spend 87 minutes in slow wave sleep, 13 minutes or 18% longer than deconditioned people.  For more details on sleep and recover, and the significance of sleep phase, please refer to my August 2009 Running Research News (volume 25 issue 6) article on “How Running Affects Sleep and Vice Versa”.


Use Of Heat and Cold Contrast Therapy


In heat and cold contrast therapy, the athlete applies heat to the legs (a heat pack, a hot water bottle, or a hot tub) for 2-3 minutes and then applies cold (ice cups, cold packs or cold bath) for a similar amount of time.  This can also be simulated in the shower by flushing hot then cold water over the legs and hips.  This cycle can be repeated 2-5 times.  This contrast therapy is believed to improve blood flow to the muscles (Bompa 1999), eliminating lactate that has accumulated in the muscles (Calder 2004), reducing inflammation, reducing delayed onset muscle soreness (DOMS) and pain relief (Bompa 1999), and help the runner relax psychologically.  Physical therapists will tell you the best time to apply contrast therapy is within 20-30 minutes of finishing your training run.
Sauna- Closely related to contrast therapy, taking a sauna bath is believed to have recuperative effects. 


For example, DeVries et al. (1968) found that the heat of a sauna relaxes muscles.  The electrical activity of the muscles was reduced bringing about lowered muscle tension.  Anything that lowers muscle tension should encourage relaxation and help recovery.


Massage Therapy


The use of massage therapy by runners of all levels is widespread.  Whether the laying on of hands actually helps heal damaged muscle tissue in the lower extremities, thus speeding up recovery time, or whether it has a relaxation effect of the runner has yet to be determined.  Other benefits of massage therapy are claimed to be improved blood flow to the legs, relaxation of muscles, enhanced nutrient and oxygen delivery to the muscles, increased removal of lactic acid, improved flexibility of the muscle and connective tissues, breaking down of scar tissue, and a kind of pre-emptive therapy on “knotty” areas that are tightening-up and that could become injured.  However, the research on the recovery properties of massage therapy is disappointing. 


Results suggest that it is either ineffective or has only limited influence on DOMS (delayed onset muscle soreness) and muscle repair and swelling.  Studies by Galloway and Watt (2004), Smith et al. (1994), Dawson et al. (2004), and Weber et al. (1994) concluded that the effects of massage are minor or transitory.  There is one promising study by Zainuddin et al. (2005) that found that massage was effective in alleviating DOMS by approximately 30% and reduced swelling.  Regardless of the scarcity of evidence, massage is a harmless and relaxing modality that certainly cannot harm the runner, and may have some benefit.


Running Shoes


Treat yourself to a new pair of running shoes … right now!  While you’re out pounding the road, it’s not the lightness of the running shoe that is important but what’s between you and the road.  Chances are that your current pair has lost its cushioning—the Ethyl Vinyl Acetate (EVA) material in running shoe midsoles breaks down within a few months, and somewhere around 600-800 miles of running.  You’ll feel it when your shoes are losing their shock absorbency—suddenly they’ll feel hard, like you’re running on wooden planks.  If you’re a heavier runner (>160 lbs), or if you pronate severely causing excess wear and tear on your shoes, you’ll chew through your shoes a lot faster.


A biomechanist friend of mine, who is a runner herself, told me about an interesting way that she addresses the problem of running shoes breaking down.  She has several pairs of shoes, including different models that she places on a “shoe tree”.  Every day she wears a different pair of shoes, giving the other shoes a chance to recover.  She also believes that wearing different shoe models exercises her legs through a slightly different range of movement, thus widening her “band of movement” as she runs.  This helps maintain her kinesthetic and proprioceptive awareness, and keeps her injury free.  It certainly has helped her, because she has been running for years without injury.


Finally, some advice to help you avoid what many a runner has found out the hard way.  The phrase, “You get what you pay for”, very much applies to running shoe purchases. 


Generally, the more expensive the shoe model, the more comfortable and the more cushioning and motion control devices it will have.  Don’t skimp on your running shoes.  It’s okay to buy top of the line running shoes, in fact I strongly recommend it.  The extra expense will be more than compensated for by the extra comfort and extra protection that the higher quality shoes offer you.


Running Surfaces


Consider the surfaces you typically run upon.  Biomechanists have a nasty way of reminding us of the brutal facts of running.  They define the total force that your body (primarily legs, hips and back) absorb while running by multiplying the total number of steps you take on a run, by the amount of force you generate with each step.  Considering that every time we land, our body absorbs the impact of 1.5-3 times our body weight (depending on our speed), the total impact adds up to tens of thousands of pounds, even over a short distance like 5 miles.  Shocking!  No wonder 60% of us get injured every year!
What can we do to reduce this impact?  Running on grass, sawdust, treadmills, or dirt surfaces significantly reduce landing shock when we run. 


Can you do some trail running or at the very least jog around a large grassed sports field?  (Soccer fields are ideal).  (For more details please refer to my article in June/July 2009 Running Research News (volume 25 issue 5) “Seven Reasons Why Every Distance Runner Should Train on Trails”).  Concrete should be avoided at all costs, and asphalt is only a slightly better running surface, so minimize this.


Tweaking Our Training Program To Ensure Recovery



Highlighted above have been the excellent preventive measures that we can use in our daily routine to ensure adequate regeneration and recovery.  These have included getting quality sleep, using heat and cold contrast therapy and massage therapy, wearing quality running shoes and replacing them often, and running on softer surfaces when possible are all.  But how can we adjust our training schedules to allow for adequate recovery?  First, understand that the real key to recovery is avoiding overtraining; i.e., prevention is the most effective method.  What are some of the adjustments we can make to our training schedules to enhance our recovery?  Here are five key rules to follow that will make a big difference.

Highlighted above have been the excellent preventive measures that we can use in our daily routine to ensure adequate regeneration and recovery.  These have included getting quality sleep, using heat and cold contrast therapy and massage therapy, wearing quality running shoes and replacing them often, and running on softer surfaces when possible are all.  But how can we adjust our training schedules to allow for adequate recovery?  First, understand that the real key to recovery is avoiding overtraining; i.e., prevention is the most effective method.  What are some of the adjustments we can make to our training schedules to enhance our recovery?  Here are five key rules to follow that will make a big difference.

1.  Plan A Regeneration Week Every Three Or Four Weeks Into Your Training Schedules


The use of a periodized program is the one major change you can make that will have a tremendous effect on your overall recovery (Norris and Smith 2002).  Periodized programs are simple to design.  Schedule one week of lower intensity and shorter duration running every three (or four) weeks.  This ensures adequate recovery of muscle tissue, refueling of your energy reserves, relieves the monotony of your standard training schedules, and gives you a psychological break from rigorous training.


How slow should your training efforts be during the regenerative week?  Nice and easy, about 60% to 70% of your maximal heart rate.  It should feel like you are cruising well below your standard “hard” training pace, and you should be able to talk comfortably while running.  You should not feel drained after these recovery runs.


How much should you shorten your training efforts?  Aim to reduce your standard daily training distance by 25% to 50%.  By reducing your distance and pace you will have lots of energy by the end of this week.  You’ll also find that in the following week you’ll feel renewed and your training pace should be faster than normal.  Runners are often concerned that they’ll lose some of their fitness when they cut back temporarily during their regeneration week, but have no concerns here.  In fact, numerous papers on carbohydrate loading and tapering show that a few days off, or of reduced running, actually improves performance as the muscle tissue recovers, rebuilds, and stores more glycogen (Costill et al. 1985).


One final word about using periodized schedules:  our bodies do not follow schedules perfectly, no matter how well designed.  There will be times when the runner will have to deviate from the schedules because recovery may take longer than anticipated.  Having a fatigued athlete sticking to his schedule invites further fatigue and perhaps poor health.


2.  Follow The Hard-Easy Principle Of Recovery Training


Recovery doesn’t just consist of taking a day off from running here and there, or doing a short easy jog occasionally—there’s far more to it than that.  At the very least you should follow a hard training effort with one or more easier training sessions.  Your recovery runs should be done at a lower intensity than your hard workouts, with the objective of enhancing your recovery.  This is a good time to let you in on a little realized fact—a long training run, even if at a moderate pace, is still considered a hard run.  Long runs deplete your carbohydrate stores and cause considerable muscle damage—definitely qualifying them as hard runs.  Thus, recovery from extended distance runs is essential before you do your next hard run.


3.  Don’t Be Afraid To Take A Day Of Complete Rest When Needed


Back in the 1970s, a runner in my former running club confessed to a training program where he took one rest day each week.  The rest of us (in our over-trained state) openly mocked him for such unmanly behavior.  However, he had the last laugh going on to represent New Zealand in many international races on the track and road.  His coach obviously saw above the unbending of the fanatical Lydiard training doctrine that reigned supreme in that era, and caused many runners to over-train.  His athletes shined through as a result.  Now I’m a Lydiard disciple to the core, and even had the honor of having Arthur Lydiard coach me at various times in my running career.  But I did notice that the majority of distance runners around me were grossly over-trained and fearful of taking any time off to allow recovery.  Not allowing for recovery was simply the prevailing attitude at the time and it was almost impossible to question the Lydiard doctrine if one lived in the heart of Lydiard country (Auckland, New Zealand).  The fact is, there is no one-size –fits-all training program, and many of us got caught up in the 100 miles per week mania, even if we were physically unable to handle it.


4.  Only Train Hard When Your Body Is Ready To Train Hard


If you’re fatigued while training hard, your body will not adapt properly and your immune system will be impaired, making you more susceptible to any bacteria and infections.  In my keener days, I’d run 100-120 miles per week often for 8 to 10 weeks and wonder why I regularly got sore throats, colds, or the flu virus of the month.  This happened like clockwork about every 6-8 weeks.


5.  Recovery Starts At The End Of Your Training Session—The Cool Down


A warm-down (known as cool-down in the U.S.A.) is a grossly neglected technique for speeding up your recovery.  It is a phase designed to adjust your body from exercise to rest.  The cool-down has many positive effects including bringing heart rate and blood pressure down to normal, preventing pooling of blood in the legs, reducing O2 from the tissues, speeding up resynthesis of waste products and metabolites that have built up during exercise, allowing the muscular system to recover after strenuous exercise, and help us psychologically unwind after our training efforts.  A basic cool-down should include decreasing, light aerobic activity (such as 5-10 minutes walking) followed by some light stretching and relaxation exercise (such as yoga poses or stretches).


6.  Recover From Races


The rules are simple for recovering from a race, rest or jog until you’ve recovered.  This means your legs will no longer be stiff and sore, there will be no point on your muscles that are sore to the touch, and you will have regained your energy for daily activities.  Cross training at a low intensity can really help with this.  For example, cycling, deep water running (Calder 2004) and walking on the elliptical trainer are all non-impact aerobic activities that do not stress the legs, while maintaining your cardiovascular fitness.  Avoid weight training for your legs until they are fully recovered.


7.  Allow For Psychological Recovery From Racing and Training


There are many studies on the close interrelationship between over-training and under recovery, and the necessity of mental recuperation after stressful training and competition (Lehmann et al 1999).  These papers examine the need for athletes to become self aware of the various mental and emotional stressors in life, as these interfere with recovery.  As you might expect from your own observations of people under stress, the individual athlete’s ability to deal with these stressors vary tremendously from person to person, and thus a minor irritant to one runner may be a major problem to another (Kellmann and Kallus 1999).


8.  Use A Heart Rate Monitor To Assess Recovery


The use of resting heart rate and the heart rate monitor are now commonly used to assess whether a runner is working harder than normal to achieve the same pace and distance (i.e., under recovered).  Early morning heart rate should be established over several mornings upon waking up.  The average should be calculated, and on ensuing mornings, if the resting heart rate is elevated by more than 5 beats/minute, it is a reasonable indicator that the runner is still recovering from the previous day’s training.  The runner can also establish normal cruising pace heart rate, and when training, if this heart rate is significantly elevated, it could be a sign that the runner is incompletely recovered from the previous day.  Finally, the role of over-training and under recovery needs to be discussed. 


Although they are two different beasts, their end result is the same—the runner does not recover between training bouts to get maximum adaptation, and in many cases, will invite illness or injury.  For a complete list of recovery strategies from overtraining, refer to my article in the June/July 2008 Running Research News (volume 24 issue 5) “Overtraining in Runners--Signs, Symptoms, and Prevention”.


These, then, are the main players in recovery—a training principle that is grossly neglected in many runners.  For the coach and runner reading this, I’d remind you of one thing- recovery is NOT an optional training principle.


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