The great disagreement I have with Hadd's training--though it very solidly covers the aspect of aerobic development--is it's seeming neglect of maintaining or improving basic leg speed and mechanical efficiency at short distances (800m-1,500m).
You NEED efficiency at 400-800m pace even IF you NEVER race these distances because good ability at these shorter distances increases your margin at all slower speeds. If you can run 13 seconds for 100m and 15:00 for 5,000, you can, by merely maintaining current velocity at VO2 max and (using several weeks of focused workouts on short, steep hills and gradually sloping downhills) improving your 100m time to 12.8 shave 10 seconds from your 5K time (50 100's).
Here are 2 articles from John Kellogg on this topic. None of these exercises compromise your work towards aerobic efficiency:
"Quickies
Set aside one or two days per week to do buildups or strides. Keep these less than 35 seconds in duration. Do them with the wind, if any, jogging back to the start between each. Some can be done off the track, but the really fast ones might as well be done on the track so as to get the fastest possible speed for the given effort and to reduce risk of stepping in a hole (grass) or pounding too hard (road). Do 2-3 sets of 5-6 reps, getting faster as you go, so the last ones in each set are really fast but still mechanically efficient (by the end of a set, you should be pretty well warmed up and ready to let some of 'em rip). Jog several minutes between sets. Be sure to shut down a rep before you tie up or before your form starts to break down. You want to "imprint" proper form and relaxation on your nervous system; ergo, tying up or flailing about is counterproductive. Concentrate more on quick feet and feeling light and loose.
Once every 2-3 weeks, do the above workout using two sets of strides AND add a 2-7 min. time trial following the second set of strides. Run at about 95% effort - this will probably be about the pace you could maintain for TWICE the distance you are running if you were really hammering as hard as you could. For example, if you're currently in 9:00 3,200 shape (that means on THAT day, NOT your all-time PR) for an all-out race, you might tack on a 1,600 in about 4:30-ish after your second set of strides. Vary the distance you use on these short time trials each time, so you can get some pace variety and work different muscle fibers. Don't overdo these things; only run them every other week at most. This practice will get your HR up high enough to preserve a fairly high VO2max without being as stressful or as anaerobic as hard interval training would. If you keep a "95% effort" mindset on these trials, you should have no risk of peaking out early. This stuff is just there to keep a small middle-distance component in your base training.
Another thing you can (and should) do is to run 4-6 relaxed, progressively faster buildups or strides before any planned tempo runs or other faster aerobic running and add a few more of the same in the middle of the cool-down jog after those faster aerobic workouts. If you haven't PLANNED a fast aerobic run but find yourself spontaneously flying into one because it feels right, you can still add a few strides during the jog afterwards.
You should always do this faster stuff in racing flats or in extremely lightweight, flexible trainers. This will give you the best pre-stretch of your ankles and will develop strength and integrity. Plus, you'll be going faster in racers with no additional effort vs. heavy, restrictive trainers. A variation of this is to do some very light BAREFOOT strides every now and then. Obviously, you need to be sure the running surface is soft and smooth and free of rocks, sticks, etc., and you don't want to overdo the speed or volume on these the first time you try them.
Remember, none of this stuff is supposed to be highly anaerobic. If you're tying up or trying to beat some pre-determined time on the stopwatch, you're approaching it incorrectly. Relax, relax, relax - but do SOMETHING about your short speed during base training. You can't expect to suddenly get comfortable at high speeds during the last few weeks of a competitive season if you haven't kept in touch with faster stuff previously.
Speed maintenance involves a moderate number of repetitions of 10-40 seconds using either a buildup format or an even speed. The idea is to enlist a large variety of muscle fibers without exhausting the creatine phosphate supply. The intensity can be easy to moderately hard, depending on the time of year, the intent going into the workout, and whether a competition is imminent.
Buildups are usually run in 2-3 sets of 5 or 6 reps each, with a jog period between sets. Following the standard warmup jog of at least 12 min., the buildups can be started without any stretching. By starting each rep (and each set) slowly and finishing faster, the heart rate is allowed to come up very gradually (preserving the creatine phosphate) and the muscles themselves warm up comfortably. Using a jog period between sets and starting the second set slowly again (but a little faster than beginning the first set) eliminates the possibility of lactate accumulation and relaxes the neuromuscular system briefly so that the second and third sets can be performed with increased mechanical efficiency.
Even-speed runs can be done as strides (15-25 secs. each) or as sets of 200s. Strides are more often used as part of a warmup before a hard workout or a race to help determine the correct starting speed. Sets of 200s can be used as a moderately hard workout during base training (when hardly any other fast running is done) or as the first fast-paced workout following a long run or a race. Normally, 2-3 sets are used. More than 3 sets results in too much lactate production to serve the purpose of speed maintenance, which in part is efficiency at medium to fast speeds. During sets of 200s, the pace should be made slightly faster on each successive rep in order to recruit as many muscle fibers as possible throughout the workout. Speed maintenance is often called "neuromuscular specificity" training when it applies to a certain goal race pace. Workouts which do something about the speed component should be run at least twice per week during base training (more often if at altitude and/or confined to trails or snow).
Running longer than about 40 seconds at any pace which maintains or improves speed will produce enough lactate to be counterproductive to the goal of sessions. Reps of over 40 secs. are used as lactate tolerance training.
Examples of Speed Maintenance Workouts
2-3 sets of 5-6 x 100 meters buildups (with the wind if it's windy), starting slowly and making each rep slightly faster than the previous one, jogging back 100 between reps, 1/2 mile to 1 mile jog between sets.
As with all speed maintenance repetitions, the goal of this workout is to reach the fastest speed which can be attained without sacrificing mechanical efficiency, without tapping into the creatine system, and without incurring any significant oxygen deficit. This is an easy enough workout to be useful as the first fast session following a tough race or very long run or for off-season, very high mileage weeks. At least a few buildups should be employed 4-5 days per week during periods of otherwise extremely slow running (such as when attempting extremely high mileage or when running on trails at very high altitude).
All buildups should be run relaxed, with the jaw loose, the elbows in, the eyes looking straight ahead, and with a natural running motion. Staying tall is ideal, but it may be counterproductive to make a forced effort to do so. The basic style and foot strike pattern should be akin to a 5,000 meter race. As the speed increases near the end of the faster buildups, the style will naturally shift toward more of a 400/800 pattern.
One purpose of buildups, as mentioned, is to keep the CP store intact by gradually warming up into the workout. The first reps of each set should be the slowest in that set. Each rep should start at a jog pace and smoothly accelerate so that only the final 20-25 meters involves any real speed. It's best to gradually tail off, as well, rather than coming to an abrupt stop.
2-3 sets of 5-6 x 200 meters starting at about 5K race pace and going roughly 1 second faster on each successive rep (with the wind if any), jog 200 between reps, jog 1/2 mile to 1 mile between sets. Each set can be started with a 200 at about 1 second faster than the first 200 in the previous set.
Reps run in this fashion are often called "cut-downs". They are not buildups; a continuous speed should be maintained throughout each 200. They are also not meant to be specific training for any particular event, or even any precise speed, for that matter. What they do is recruit all manners of muscle fibers at many different speeds, while keeping lactate production to a minimum.
Ken, a hypothetical top-level master, runs 5,000 meters in 15:00, which is a pace of 36 per 200. An effective "cut-downs" workout for Ken might entail 6 x 200 in 36-35-34-33-32-31, with a 200 recovery jog after each rep, followed by a short break of about a mile jog, then a second set of 6 x 200 in 35-34-33-32-31-30. Obviously, it's difficult to run exactly 1 second faster on each successive 200, but a small pickup of some sort is the general idea. By starting no faster than 36, Ken keeps his creatine phosphate (CP) stores intact, and as he warms up into the workout, he can squeeze the speed down without tapping very deeply into that CP reserve. After the break between sets, he starts over at a medium speed again (but a little faster than the first set, since he's pretty well warmed up at this point).
Ken could do a third set of still faster 200s (depending on how much speed he's retained in his 40s - this isn't meant to be a very hard workout; only a fast one). If he felt that he would have to sacrifice technique and efficiency by cutting down to 29, he could do 3 sets of 5 instead of 3 sets of 6, and would only have to cut down to 30 in the last set. That may not sound like much of a variation, but most runners are well aware that a second faster in a 200 makes a huge difference in effort and relaxation as top speed is approached.
Ken might choose to stop at 2 sets if he had an important competition in a few days, or if he had just run a long race a few days before. Or he might not have performed this type of workout in awhile and wouldn't want to overdo it. Or he might just not have it on this particular day. It's important to finish speed maintenance workouts while still feeling fairly sharp and strong rather than feeling cashed.
* 10-15 x 75-95 meters uphill @ 3%-5% grade (this is a rise of 10-16 feet in 100 meters) at about 3,000m-2 mile race speed/jog down slowly after each rep.
These runs should take about 12-15 seconds each, so few runners will get as far as 95 meters. The grade should not be so steep as to sacrifice speed or risk Achilles tendon trouble, but it needs to be enough of an incline to get a good pre-stretch of the ankle.
A complete warmup period (including some buildups) is needed for this workout. These reps are not buildups themselves; they are fast enough throughout that creatine phosphate would be used if a sufficient warmup were not taken. Owing to the short duration of each rep and the low density (rest periods up to 3 times longer than the runs), not much overall lactate will be produced.
The chief purpose of this exercise is to develop ankle power, flexibility and drive, and to increase knee integrity. It's important to keep from leaning into the hill (that's one reason for not making it too steep). Staying fairly upright forces the muscles in the ankle and knee joints to perform the correct movements.
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