Physiology of Run Training

     Since it's the end of my semester, and I am just starting training again, I decided to make a series of posts regarding the training for triathlon (or the sports individually) from a physiological perspective and how it relates to what we as athletes do every day.

     I want to start with running for a few reasons. First, it's usually my favorite activity, I am currently coaching at high school team, and I have read a lot into the physiology of it and include that in my master's thesis.

     For triathletes, usually the "season" takes off in early spring and culminates around the fall. Most athletes, myself included, will train for two peaks within a season; one in the late spring, and the second in the fall. Because of this, I think it is very important to start finding the events in which you wish to race early, and you can plan your training from there.

     I think it is rudimentary to look at phases of training as black and white. Traditionally, a season of run training may look something like: 6-8 weeks of base, 4-6 weeks of aerobic specific training (tempo runs, fartleks, etc), and finally shorter speed training for the last few weeks of the season. While this is a pretty good plan, I think it is important to blend each of these phases while training.

    Backing up, lets delve into some of the physiology behind running fast. Your training should reflect well upon your racing goals. The first variable of importance will be lactate threshold. This is the point where your body cannot buffer lactic acid anymore because you are consuming more oxygen than you can take in and process. When exercising at a lower intensity, you are generally in what is known as "aerobic" exercise. Enough oxygen is present to fulfill the requirements of glycololysis (the method for which ATP is produced). As the intensity increases, the body requires more oxygen to keep up with the muscles' increased work load. At a certain point, the intensity crosses a point known as the lactate threshold, and the lactic acid produced as a byproduct of glycolysis can no longer be "buffered" by carnosine, and the body can only exercise in this "anaerobic state" for a few minutes. Because this lactate threshold pace is a pace that many 5k-10k runners and spring to olympic distance triathletes must operate in, I think it is very important to be cognizant of it and how to improve it.
   
    In order to improve lactate threshold, it is good to run at or around that pace for an extended period of time (no surprises here). The best way to know this pace would be from a lactate analysis in a physiology lab, but it can be reasonably estimated from various online calculators. One of my favorite ones is http://www.mcmillanrunning.com. I think it can overestimate training paces at times, but it is not a bad idea to follow. To improve lactate threshold, tempo runs can help tremendously. During the winter or build season, I like to do longer tempo runs of 8-10 miles slightly slower than lactate threshold pace because it works a bit more on strength that will be called upon later. I will shorten those tempo runs to the calculated lactate threshold pace as the spring comes and races are closer. These workouts are a staple of my "base training" plan. I like to try to get on soft surfaces and run them off the track during the winter, but as they approach pace, I think they are good to do on a track where you can consistently measure times. Keep in mind, these runs are getting faster through the year, and by race season, they are to be done at a pace that will lower your lactate threshold or "LT". If you run way faster than your threshold, you will be unable to complete the 20-30 minutes of LT running, so it is good to lock into your goal LT pace. This is generally slightly slower than goal 10K race pace. Keep in mind, these runs at LT are only a piece of the picture.

    Next up is the long run. For triathletes, I think it is important to get a long run in for musculophysical reasons. Running long (25% or so of your weekly mileage). The long ride for triathletes takes care of some advances of long runs because your body becomes more efficient at fueling itself, but I think they are both necessary. For running specifically, the long run is a great workout and should be a staple of most build phases. Not only does it make the legs stronger physically (often a limiting factor in races 5K and up), but it also is a good mental test. I like to get 2- hour long runs in the winter at a pretty good base pace. You can find some recommended base paces, but from a physiological perspective, you want to run fast enough to be working, but not getting close to LT or a workout pace. From early Lydiard running days, the long run was emphasized for all runners racing events from 800 meters to the marathon. I believe there is a good reason to develop the aerobic system for all athletes as well, and the long run is a good method to improve musculoskeletal fitness. Furthermore, for marathon and ironman athletes, the long run allows for practice of proper fueling for the race. Practicing eating those foods which you hope to consume in the race. The long run can continue well into the season, but during the race season, the total distance should decrease with the intention of maintenance rather than lengthening.

     VO2 max is sort of a "buzz word" in running physiology. VO2 max is the maximal uptake of oxygen your body can consume during exercise. There are a number of apparatuses a VO2 max test may be done on, but for most, a treadmill will elicit the highest number (because more muscle groups are being worked, and therefore more oxygen must be proliferated). The VO2 max test consists of slowly increasing the grade and speed of a treadmill while monitoring VO2 and respiratory exchange ratio. (the ratio of oxygen consumed and CO2 expelled). A VO2 max test may also be estimated from an all out 6-8 minute run. There are more tables that will estimate VO2 max from 5K times. I do not think the actual number is completely necessary, but rather training of this "physiological ceiling" is important. Your VO2 max is as efficient as your body can be, and it is not highly trainable. When you do VO2 max workouts, they are very high intensity, and should be introduced about 3-4 weeks before your races start. As the season goes on, it is important to work more on VO2 max workouts than the others. An example of a VO2 max workout that I like is 6-8*600 or 5* 1000 meter repasts around 3200 or 3k pace. This should be a pretty intense session, and the rest should be 3 minutes or so. I like to get the 'feel' of running at this VO2 max pace. it is pretty well corroborated with 3K race pace, so it is likely faster than you will ever be running in a triathlon, but it is important to be efficient at this pace, so slower paces also become more efficient.

     The last topic I want to mention is maximal speed. I think there are usually two very polar schools of thoughts on this. One thinks it is of upmost importance in olympic distance racing and 5k-10k work, and the other thinks it is completely unimportant. As usual, the truth lies in the middle. It is important to have a fast top end speed for efficiency, but should not be the top point of emphasis. For this, during the build phase, 6-10 strides after maintenance runs help to maintain foot speed. Later in competition, workouts such as 10 200s with 200 recovery at mile race pace, followed by 10 200 uphills are good ways to maximize neurological efficiency and maximize your speed. These fast pace efforts can include "hill sprints' or 10- second hard efforts up hills at the end of maintenance runs to improve biomechanics and neurological efficiency.

As a finishing part of this post, it is important to run fast if you wish to race fast! Just consistent slow running can only get you fit, but not sharp. Doing faster pace efforts are beneficial to everybody! But, caution should be taken to ensure proper recovery from them.

Here is a sample outline of a mini season (6 month block) of just the run training.
Weeks 1-6 include building mileage and varying the paces of runs. Not every run should be the same pace! Strides should be done every run and hill sprints 1-2 times per week. A weekly long run should be added (20% of total mileage for runners only, and likely more for triathletes since they are not getting high running numbers). On days when you feel good, pick up the pace and see how it feels. Designate one or two days where you can do a fartlek such as 1 minute on/1 off, 2/2, 3/3, 4/4 and back down.
Weeks 7-12 Should continue emphasis on strength with longer LT runs. Find the level for which you are comfortable to run a bit slower than your LT pace for 40-60 minutes. Long runs should stay at a good distance. Strides should be continued. Hill repeats are another good workout to do for strength during this time. I would structure a week something like
     M- Maintenance run with 6-10 strides, T- Hill repeats, W- X train or easy run Th- Maintenance run with strides, F- 40-60 minutes slightly slower than LT pace Sat- Easy and Sun- Long run
Weeks 12-16 Now, racing is usually looming, and it is important to begin running at a pace where you want to race. Tuesdays can be switched for harder VO2 max type work, and tempos can be slightly shorter but faster. The long run is less important to be lengthy, and recovery becomes more important.
End of the cycle Continuation of what you are doing with the inclusion of some fast efforts well below race pace and all other workouts look to recover. 10- days out of a peak race, I like to do a hard session to lower muscle pH and simulate the race conditions well.

That is my running philosophy and some vague ideas about running. If you have any specific training or physiology questions, please do not hesitate to e- mail me at dan.feeney31@gmail.com