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Medical Long distance running

  1. Jun 19, 2009 #1
    On one trail I can run 3 miles almost continuously, with small 20 second breaks. However, when I get on the 8 mile trail, at about 4 or 5 miles into the run, my legs start to hurt very abruptly and feel really heavy. My cardio is good enough to keep going, but I'm unable to move my legs faster. I have to walk frustrated, sometimes limping the rest of the trail, when I could have ran all the way.

    I'm probably missing something. Why legs die like that? and is there an exercise of some sort or a diet to improve this?
  2. jcsd
  3. Jun 19, 2009 #2


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    Lactic acid build up?
    Try starting slower
  4. Jun 19, 2009 #3


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    Your problem is that you are in a dream. The solution is to wake up.
  5. Jun 20, 2009 #4


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    I am currently in exactly the same position. Except that I've been training for a 6km race (3.75 mile) and my legs suddenly hit a massive barrier between 4.5-5km (2.8-3.1 mile). I'm thinking it would have to be lactic acid build-up as that seems to be the answer of the day for anyone trying to understand the problem... But really, I also run the 800m race and of course hit a lactic acid barrier in that one, without the leg pains.

    I find it amazing that what you have described is the exact same wording I used too. For myself, it mainly hits my calves while I feel a bit of burn in my thighs - not very significant compared to the calves though. It's as though they become "un-springy" and cannot propel me anymore, for as much as I try, I can't keep up the same pace as I did in the last 3/4 of the race.

    And yes, I too feel like my cardio is perfectly fine and still has much to give.
  6. Jun 21, 2009 #5
    I guess this must be it, didn't know much about Lactic acid before

    The first thing I thought about when started running afters years of inactivity is that a marathon is two months away.

    yes, indeed, after a while on the trail you sort of fall into your comfortable pace where breathing and transfer of energy is optimum and you can continue on in that state for longer time, without any breaks.

    after your legs brick, you still want to maintain your pace but can't
  7. Jun 22, 2009 #6


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    Yeah and it's quite frustrating isn't it :cry:

    That recent long distance race I competed in where my legs failed me after 5km in the 6km track, I was pacing myself with this guy I run with, he of course beat me since he didn't hit a barrier like I did. I took him on in a 3km race and since it was half the length, we were able to keep up a slightly faster comfortable pace. This time I beat him. I didn't hit any barriers and was able to out-sprint him in the last leg.

    Maybe I'm just not cut-out for long distances just yet? waht have you tried shorter distances and noticed the same thing?
  8. Jun 22, 2009 #7


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    Are your legs cramping? You can help that situation by eating more bananas, and hydrating more with Gatorade, etc., both before the run and during the longer runs.

    Also, are you cross-training at all? That can be very helpful for your overall cardio and muscle endurance, plus it helps to break up the workout week and keep it all more interesting. Consider mixing in lap swimming and bicycling (road or MTB) some days. I find that MTB riding and running complement each other well, and each helps my endurance and power in the other.
  9. Jun 22, 2009 #8

    Andy Resnick

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    Assuming the trails are comparable- one doesn't differ in hills vs. the other, for example- what you seem to be describing is known as "fatigue". Fatigue is the inability to maintain a muscle contraction, and can be casued a a number of problems, including impaired excitation-contraction coupling, inadequate O2, or inadequate fuel. "Hitting the wall" means the available glycogen (oxidative fuel) has been depleted, inadequate O2 supply can be due to a lack of microvasculature, and impared coupling due to intracellular Ca++ depletion.

    It's hard to say which of these problems is causing your fatigue; it depends on your pace, and if you are running near aerobic capacity. The need to take breaks indicates to me that you are probably at or near aerobic capacity; your body will, while training over time, generate more capillaries in the muscle to supply the fibers with oxygen, increasing your endurance.

    Cramps are another sign of inadequate O2, if that helps. Here's a decent online column:

  10. Jun 22, 2009 #9


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    The idea is to go slower and gradually extend the distance.
    Your body burns glycogen in the muscles when it needs energy quickly and fat otherwise, by running more slowly you keep your muscles in low power fat burning mode. When you run out of glycogen you stop = the wall.
    The idea is to train your muscles to an efficiency that they can run the full distance staying in fat burning mode.

    If your muscles ache rather than just feel like lead then you have gone much too fast (unless you are in a sprint) and have built up too much lactic acid (which isn't really lactic acid - but that's what runners call it!)
  11. Jun 24, 2009 #10
    What is your running form?

    Are you taking long strides or short strides. Shorter strides are better for distance running. You want compact, not elongated because you are expending more energy.

    What is your speed. Are you running the 8 mile trail at the same speed as the 3-4 mile trail? If so, you haven't built up your endurance yet to match that. Train slower and build into your speed. Your legs aren't connected to your lungs. You can have respiratory endurance, but your legs still need to catch up.

    Take more breaks. Running longer distances you should be training with more short walking breaks. Use the 10:1 (10 minutes run, 1 minute walk) as a general guideline.
  12. Jun 24, 2009 #11
    yea, bananas are loaded with carbohydrates, that consists part of my diet

    my only form of cross-training is MTB, and weight lifting, I don't do any specialized exercises, although I'd like to.

    I have improved ever since I started running, but now can't see any improvements,

    That's pretty cool

    Total lead, unable lift a foot off the ground.

    That's the problem. Average speed is about 4 mph
  13. Jun 30, 2009 #12


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    Is any value in training at specifically different speeds, and in different combinations (for running) ? A proposition is that running at a slow speed is different than running at a fast speed.
  14. Jul 2, 2009 #13

    Andy Resnick

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    Skeletal muscle comes in different 'flavors'-type I (slow-twitch) fibers and type II (fast-twitch) fibers; a muscle has some blend of the two. The idea behind running 'intervals' (http://www.sportslog.com/running-log/running-speed-work.htm) is to train both sets of fibers.

    Aerobic training, that is developing resistance to fatigue, is all about increasing the available O2. This is done by boosting the cardiac output and enhancing the diffusion of O2 into muscles by increased capillary density.
  15. Jul 2, 2009 #14
    I agree that one has to build up running long distances, slowly. What worked well for me was to first increase the number of days per week that I work out. I used to train 3 to 4 times per week, now I exercise 6 times per week. I then increased the time I run in trainings from 15 minutes to 25 minutes. Simultaneously with that, I increased the pace at which I was running.

    By increasing the frequency of trainings, you force your body to recover from trainings faster. That then gives you a more solid basis to increase the intensity and duration of each traing. What can also help is a light training a few hours after the main training to help you recover faster. I have just started to do this.
  16. Jul 3, 2009 #15


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    I go about it in the opposite way. I instead force myself to complete preset distances, and expect myself to be completely dead by the end of it, usually by keeping track of my speed, or speeding up to kill myself in the last 1km or so. I then let my body recover at its own pace and go back and do it again when I feel better (now it's every second day, a month ago I was doing it twice a week).
    It works well for me anyway.
  17. Jul 3, 2009 #16

    I'm sure that this would not work well for me :smile:
  18. Jul 3, 2009 #17


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    Unless of course your daily life requires you to be in fit shape and not fatigued for days at a time, then I understand. Otherwise, why do you say that?

    I'm pretty much sitting all day due to school and study so my life doesn't ask much in terms of being physically prepared, thus the training routine I've chosen works quite well for me.
  19. Jul 3, 2009 #18
    I exercise to be as fit as possible (on the long term). Different people may respond differently to the same training regime, so you need to experiment to find out what works best for you. In my case, I found out that I need to train very vigorously almost every day of the week.

    If you just started to exercise, then the maximum fitness level you will be at a few weeks later will be determined by the maximum amount of recovery your body can manage at the present moment, because within a period of a few weeks you won't be able to change much about how efficient the body repairs itself.

    So, you exercise, which causes damage and then your body repairs itself, but it does extra repairs, so you get stronger. The optimum amount of training is then determined by the maximum repair capability of your body, but you won't be able to change that in a few weeks time.

    If you take a longer term perspective, you should focus on expanding your body's self repair capacity. To train that, you need to exercise for some time at a level which would cause your body to become overtrained on the long term. So, you're presenting your body with a problem that it cannot deal with on the long term with its current level of self repair capacity.

    Then what will happen is that you'll notice that your resting heart rate will increase, you may feel a little more tired. If you train at this unsustainable level for, say, two weeks and then take a rest for half a week, your body will catch up during that half a week of rest. Then you repeat this, i.e. you train again for two weeks and take half a week rest. What you then notice is that at the end of the second two weeks of training your resting heart rate was less increased. So, this means that your maximum recovery rate must have increased.

    After repeating this a few times, you switch to some lower intensity training that you think you can now easily tolerate on the long term. That intensity will be higher than what you could easily tolerate before you did the intensive two week trainings.

    You may notice that you need to sleep a little longer and eat a lot more. If you then keep training for a long time, say half a year at your new training level with your increased repair capacity, you'll make huge progress.
  20. Jul 3, 2009 #19


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    That's a very clever regime Count Iblis :smile:

    For the past few months since I began training for competition (after years of inactivity) I guess I've always been in the training routine that I wouldn't be able to sustain in the long term. Roughly that first two week program you were speaking of.

    Basically, yes I have needed more sleep and food ever since. The sleep is fine but I also intended to lose weight in the process to become lighter and more competitively competent, but I don't think this extra calorie intake is helping the process. It's not that I'm fat, but being 180cm (nearly 6ft) tall and 72kg (170 pound) made me realize I'm carrying an extra 10kg more than the other strong competitors at my height. Anyway, in the first two week of training, I went from 76kg to what I am now and ever since I've just held that weight.

    My muscles are what slow me down as well. I still have the same trouble as the OP when it comes to running. I keep going at it till my legs give in, while my lungs still feel perfectly capable of continuing on. In the very beginning, it was the opposite. So all I'm doing in my rest days is waiting for my body to repair my burnt out legs. Sometimes I push myself to the point that I'm limping for the entire next day. This only happens, however, when my legs feel like dead weights during my runs.
  21. Aug 28, 2009 #20
    Just got back from a 10 mile run. Lately I've been drinking 1 cup of strongly brewed black coffee before lifting weights and running. It definitely works for me. Caffeine is believed to prevent muscle fatigue and I am certainly seeing effects--running longer without getting tired, lifting more reps before getting tired, etc. Give it a try.
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