Lactate threshold running speed

This New Zealand research shows why it makes sense to boost your lactate threshold running speed

Okay, everybody knows by now that lactate-threshold running velocity (LTRV) is a great predictor of performance prowess in endurance events like the 10K and marathon. After all, LTRV, which is simply the running speed above which large amounts of lactate begin to accumulate in the blood, likes to hang out at about 2 to 3 per cent below 10-K running speed and 5 to 6 per cent above marathon pace, and these linkages remain steadfast as LTRV improves in response to appropriate training. As LTRV rises, it simply ‘pushes’ 10-K tempo to new heights and ‘pulls’ marathon running upward – in the direction of new PBs.

However, although having a high LTRV is critical for 10-K running and marathoning, there’s no way that LTRV should be a big deal in 800-metre racing, right? I mean, to run a super 800, you want real power – rippling leg muscles, high stride rates, lengthy strides, and tremendous tides of lactate flooding your muscles as they pour out the high-wattage anaerobic energy. In contrast, when you build a great LTRV, you actually want to minimise lactate production, the total opposite. Plus, the best way to heighten LTRV is to run for very long intervals – six to 10 minutes or so – at about 10- K pace, or cruise continuously for about 25 minutes at a speed which is 10 to 15 seconds per mile slower than 10-K tempo. It’s hard to understand why that sort of training would help you blast off like a rocket in an 800m competition.

I’m sure you’re with me so far, but guess what? Our reasonable reasoning is dead wrong: LTRV is a great predictor of 800m prowess. As your LTRV goes up, your 800m time improves dramatically. And as your 800m ability crests, so will your capacity to run a really fast 5K!

The Otago 800
You’ll hear more about the connection between 800m and 5-K success in a moment. For now, here’s the story behind LTRV and your best-possible 800m running: At the University of Otago in New Zealand, Gordon Sleivert and A. K. Reid recently evaluated 17 middle-distance runners (12 males and five females) of good ability (VO2max =3D 63.1). The 17 athletes competed at 400, 800, 1500, and 5000 metres and were also checked for LTRV, VO2max, and running economy (the three key physiological variables which best predict middle-distance running success).

Well, we usually preach that aerobic development is critical for 800m performance (since about half of the energy needed for the race is generated aerobically), but, surprise, surprise, Sleivert and Reid found that VO2max was totally unrelated to 800m times. In other words, runners with high VO2max values didn’t run faster than those with low figures. So much for the oxygen sermonising! 800m times also didn’t depend at all on running economy. If you’re following along, that shouldn’t be a surprise. We’ve already found out that being able to use oxygen at high rates (e.g., having a lofty VO2max) is no big deal for the 800. So why would we expect that being parsimonious with that common atmospheric gas should be a big deal, either?
But LTRV? Since aerobic metabolism (either high, for VO2max, or low, for good economy) is no great shakes at prophesying 800 times, then ‘anaerobic’ (oxygen-independent) energy creation must be the prime thing. And anaerobic metabolism means getting out there on the track and letting it rip, flooding the muscles with lots of lactate and creating all sorts of energy without utilising much oxygen. On the other hand, having a high LTRV means running fast without too much lactate. As we mentioned before, those are opposites, so how can LTRV be so important for 800m times?

Just the facts
‘If someone has a high LTRV, then they can run faster with less lactate accumulation, compared to someone with a medium or low LTRV,’ says Dr. Sleivert, who is a fine coach in addition to being a keen kinesiologist. Makes sense, doesn’t it? But just in case it doesn’t add up to you, let’s use an extreme but edifying example: If someone has an LTRV of 300 metres per minute, they can run an 800 in 2:40 (which is exactly 300-metre per minute pace) without getting the lactate waterfall going. On the other hand, someone with a lower LTRV of 250 metres per minute would produce huge dollops of lactate at 300-metre per minute pace and experience mega amounts of fatigue when trying to run the 800 in 2:40. The 300- LTRV person would be a much better 800m racer than the 250- LTRV competitor.

‘To put it another way, remember that below LTRV your lactate level is pretty placid and constant while above LTRV your lactate level rises steadily and predictably as your running pace increases. That means that as your LTRV gets faster, you have more running speeds with calm lactates (those are all the ones which are below LTRV), and – most importantly – your running speed at any given lactate concentration is faster. As a result, you can run more quickly without excessive fatigue,’ observes the man from Otago.

Putting it into practice
Here are some good examples of that: Let’s say that when you run the 800 in 2:00 (a nice thought!), your lactate concentration is 14. However, you improve your LTRV so much that lactate can only get as high as 12 when you zip through 800 metres in two minutes. You can still tolerate a lactate level of 14, though, so – hey! – why not stoke up your running with a little more anaerobic energy, pushing lactate up to that magic 14 number? When you do, you’ll zip through the race in just 1:55 or 1:56.

Or, let’s say your LTRV is 300 metres per minute, which produces a lactate concentration of 4, and you run your 5Ks at 315 metres per minute, with a lactate level of 8.. However, by following the training dictates outlined below, you raise your LTRV to 315 metres per minute. Since your lactate is now a simpering 4 mmol/litre at 315 metres per minute, and you can tolerate 8 mmol in the 5K, you do the right thing: you shoot your 5K pace up to 330 metres per minute, giving you that nice lactate buzz of 8 mmol again, and improving your 5-K time by a not-too-shabby 43 seconds.

Well, we’ve got this LTRV and 800m racing connection down pat now, and the last example shows that it doesn’t sound that much different from what we want to achieve in order to knock off some great 5Ks and 10Ks. To put it simply, you become much better as a runner if you can move really fast without churning up the lactate waters too much (eg, if you can raise your LTRV). That’s true for the 800 – and for the 5K and 10K, too.

Good lessons
And that suggests that aerobic development is important after all in the 800 (otherwise, your muscles would spew out too much lactate). We’re not contradicting what we said earlier here: the way to think about it is to realise that VO2max is not an important predictor of 800m success when you look at a group of runners. After all, the high-VO2max woman or man might not be able to generate enough energy anaerobically to compete well in the two-lap race. She (or he) could be beaten easily by the mediocre-VO2-max runner who could turn out a lot of energy oxygen-independently.

However, when we look at you as an individual, it’s immediately clear that you do have to work on your VO2max if you want to run your best 800. That’s because upgrading your heart’s thumping power and your leg-muscles’ oxygen-grabbing capacity (the two components of VO2max) is a fine way to keep you from generating too much lactate during the race. And upraising your LTRV – getting good at running fast without turning on the lactate tap – will help you even more. It’s just a question of knowing how – and when – to try to maximise LTRV.

Fortunately, the how part is easy. Key workouts for LTRV enhancement include (1) sparking along for 10 minutes at 10-K pace, with three- to five-minute recoveries, and (2) hitting 10-K speed for six-minute intervals, with just one to two minutes of recovery. Also good are sessions traditionally viewed as VO2max workouts, including five-minute intervals at 5-K pace and three- minute intervals at two-mile race pace. These sessions can be excellent for LTRV, because as they send VO2max skyward, VO2max ‘drags’ LTRV along with it.

For workout no. 1 from the preceding paragraph (10-minute intervals at 10-K pace), you would start with one 10-minute interval per workout and gradually progress to three intervals per session. For the recovery intervals, the progression is to start with five minutes and work down to three. If you don’t run 10Ks (and therefore don’t know what your 10-K tempo actually is), use a pace which is about 12 seconds per mile slower than 5-K tempo during your 10-minute work intervals.

For workout no. 2 (six-minute intervals at 10-K pace, with two- minute recoveries), start with two intervals per workout and gradually build to five. Once you’ve accomplished that, shorten recoveries from two minutes to just 60 seconds. As mentioned, if you’re a 10-K-free runner, utilise a pace which is 12 secs per mile slower than 5-K speed.

The two key predictors of 800m performance
To answer the ‘when question,’ if you’re training for 800 metres, you should do these kinds of workouts only after you’ve gone through at least a two-month period of ‘general running’, which includes some long aerobic running, a few interval workouts at 5-K pace, and a generous portion of hill climbing. And do them before you begin to focus on 400-metre-type training for your 800s.

What’s that? Well, we almost forgot to tell you that 400-metre time is a tremendous predictor of 800-metre performance, too. After all, we can’t let LTRV stand around by itself and be lonely. You do need a great LTRV, but you also need to fully develop your anaerobic (400-metre) capacity if you want to run your best possible 800. LTRV and anaerobic capacity are the ‘twin towers’ of 800m racing.

So, that means getting out on the track and doing some 200m intervals which are two seconds per 200 faster than current 800 race pace – and some 400m intervals which are three seconds per 400 faster than current 800 race pace. Such intervals will develop your speed and anaerobic capacity (recoveries from these intervals can last for several minutes; you should feel strong and ready before you begin a subsequent work interval).

To foster speed endurance (the ability to run fast while tired), you’d want to cover some 1000m intervals in which the first 800 is about 30 seconds or so slower than 800m race pace but the last 200 is at exact race pace, and also some 200m intervals at exact race pace, with only 10 seconds of rest in between. To optimise finishing power, it’s also nice to run some repeat 300s. For these, the first 100 should be easy striding, but the last 200 should be at race speed. Recoveries shouldn’t last for more than a minute or so.

Lactate stacking
Sleivert himself likes to use the ‘Lactate Stacker,’ a red-hot workout which involves warming up and then alternating 40-second work intervals (at 400m race pace), with 20-second recoveries (jogging). It’s appropriate to start with two sets of five to six repetitions of the 40-second surges, building up to two sets of 10 to 12 reps over the course of a six-week macrocycle. This session is great for developing anaerobic capacity – and the ability to tolerate acidic conditions inside your muscle cells (the kind of conditions which prevail near the end of an 800m race). Strangely enough, this workout isn’t bad for boosting VO2max either, since it keeps heart rates at near maximum for the duration of each set.

Another gemstone training session for lifting anaerobic capacity, also recommended by Sleivert, is to warm up and then pile up 200m repeats at a pace which is two seconds per 200 faster than 800 tempo, with 30 to 45 seconds of recovery. Again, you can start with two sets of five to six reps, gradually increasing to 10 to 12 reps over time.

Wait! Don’t forget that while you’re doing all that speedy stuff, you’ve got to maintain your VO2max and LTRV, too. Otherwise, you’ll start bathing your leg muscles in a sea of lactate again – and bury your mind in a mountain of fatigue. A weekly VO2max or LTRV session, along with a weekly steady run of 45 minutes or so, should be helpful here.

Oh – there’s one other thing we forgot to tell you: Sleivert found that 800-metre capability is a pretty good predictor of 5-K performance (runners with superior 800m times were also the ones with the best 5-K times, too). That’s because doing some of the things which are necessary for 800-metre running, like giving VO2max an elevator ride, lifting LTRV, and developing higher footspeed, are all wonderful for 5-K racing as well. The bottom line is that even if you’ve never run an 800m race in your whole running career, conducting some workouts which are great for the 800 will also give your 5-K running new life!
Owen Anderson