Lactic Acid Management

I liken a race to a video game.  Think of many of the modern “quest” type video games.  You have a task that involves some sort of journey through a series of challenges to get to the next level.  A race can be viewed as a journey through a series of challenges as well, with the objective being trying to get to the finish as fast as possible. 

In video games you usually have some sort of meter that indicates your “energy level” and/or “lives”.  For every challenge that you face you use up energy, and if you’re inefficient in how you ‘kill the dragon’, ‘pass through the valley of fire’ or ‘battle the zombies’ you use up too much energy and that puts the rest of your journey in jeopardy.  On the other hand, there are usually rewards for doing things well and they tend to manifest themselves in your energy level being replenished somewhat.

A race is actually pretty similar

We have to consciously of our energy level.  If we go too hard for too long too early, we run the risk of going into the red and paying too high a price and suffering for it later on.  On the other hand, just like in the video game, we can go hard and only flirt with the red zone and be rewarded with energy being “given back” which makes us feel like we’re out of danger of the red zone and more comfortable.

In paddling, unless it is an ultra-long race, we’re not so much concerned about energy levels as we are blood lactate.  If we accumulate too much lactic acid in our muscles and blood it has a similar effect as using up too much energy in the video game and we’ll die (figuratively speaking – we’ll actually be forced to slow down or stop dead in the water).  However, we can accumulate significant amounts of lactate and overcome and recover from that build-up, provided we don’t work too hard for too long.

What is lactic acid?

As a refresher, lactic acid is a by-product of anaerobic metabolism, which is a method of supplying energy to working muscles in the absence of oxygen.  When we work hard anaerobically we can go for about 90 seconds to perhaps 2.5 minutes maximum (if you’re very fit) before blood lactate levels become too high and your muscles begin to fail.  What’s happening is our muscles are swimming in lactic acid, which is being dumped from our muscles into our blood stream in a desperate attempt to get it to the liver where it can be removed.  The rate of lactate production so far out weighs the rate of removal that our muscles, if we go too hard for too long, end up awash in lactic acid and end up failing as a result.  We want to avoid this at all costs.  So, what we need to do is pace ourselves and work at a slightly lower intensity.

Below what we call the anaerobic threshold we are working aerobically.  In aerobic metabolism the energy demands of the muscle are met through a process that uses oxygen.  As long as the muscle’s demand for oxygen can be met with supply via our cardiorespiratory system we can work indefinitely.  There are no negative and limiting by-products produced in aerobic energy production.  But if we start to work harder, demand for oxygen in the paddling muscles begins to outstrip our cardiorespiratory system’s ability to supply it and we won’t be able to produce all of the required energy aerobically. There will be an energy shortfall and we’ll have to start to top up the energy produced aerobically by producing some of it anaerobically (without oxygen), resulting in lactic acid being dumped into the system.  So, lets think of our race and how hard we can go in terms of anaerobic threshold and lactic acid production.

When you go hard off the beach to the first buoy, then round the turn and try to establish position in the lead group, you’re likely working above your anaerobic threshold.  You’re producing considerable amounts of lactic acid.  If you’re really going for it, paddling at absolute max, you’ve only got a limited amount of time before you’ll feel like you’re going to blow up.  If you’re really fit that might take as long as 2 to 3 minutes, though for most of us it’s probably considerably less.  If you’re going hard but a notch below crazy hard, you might be able to last a little longer as your muscles won’t be requiring quite as much energy and so won’t be producing lactate quite as quickly.

The key is to have an appreciation of where you are in the blood lactate range at any time and know roughly how much longer you can go before you accumulate so much lactate you basically stop dead in the water.

Lactic Acid and the Intensification phase of training

Short of doing regular blood lactate testing and learning how much lactate you’re producing at a given heart rate or pace, you’re going to have to estimate.  And to do that with any degree of accuracy it means you’re going to have to do some high lactate work in training.  When we are doing an “intensification” phase of training, we’re doing this regularly.

In this type of training you start to learn where you’re at as you’re accumulating lactate and approximately how much time you have left at a given pace.  Also, as you’re doing this training, you’re slowly going to increase the amount of time you can go hard for by delaying lactate build up somewhat and by increasing your ability to tolerate or buffer lactic acid in your system.  So, as you gather more experience paddling in a high blood lactate regime you’ll begin to get pretty good at estimating how much longer you can go for at given heart rates and paces.  

The important thing to know is that just because you’re accumulating blood lactate it doesn’t mean you’re necessarily messing yourself up for the rest of the race.  If you slow down and stop working anaerobically and fall back below the anaerobic threshold you give your blood stream a chance to carry lactic acid away from your muscles.  It will carry it to your liver where it will be removed from your blood stream and converted in large amounts to glycogen (stored glucose) which can be used as fuel to make more energy.  You won’t get lactate levels back to rest level immediately, but slowing down will get you out of the danger zone.

When to Rest

Now, consider what happens if you’re going really hard off the start of a race and sense that lactate levels are rising dangerously but instead of slowing down are able to find a wash to ride in a draft train. In this case, you get to rest for a while and bring your lactate levels back under control without having to slow down.  Drafting is a vital component of racing and, if you’re confident in your ability to draft efficiently and rest while you’re doing it, you can usually plan to go out really hard in races, establish great position, get in a good draft train and then rest, bringing lactate levels under control until the next time you need to go really hard.  

I’ve been in races where it feels like I only have another stroke or two to give before I blow up and I have to stop.  I’m at the point where it’s get on the wash in front of me or it’s game over.  I’ve always managed to get on that wash, but sometimes it’s been really close.  The feeling of relief in getting over that last wave and then being able to relax is unreal.  And when I’m able to do it I make sure I really relax for the duration of the time I’m on the wash.  I probably need about 10 minutes resting on wash when I’m really in trouble with high lactate to get out of the danger zone.  But if I can stay there with the group I may never need to go so hard again in that race except at the finish.  Even when I take my turn leading it will often be at an easier pace than I might have used to catch up to or earn my spot in the train in the first place.  There will be lots more about drafting and race strategy in future posts, but the point here is it is a great place to rest when lactate levels creep up too high.

If you can’t find a wash to rest on or realize you aren’t going to catch the train in front of you, you’ll eventually have to back off and stop red lining or it’s over.  Your lactate will get so high you won’t be able to recover without actually stopping to rest for a few minutes.  In that ever happens, hopefully there is a paddler or paddlers just behind you that you can draft on and rest once they catch you and, as your lactate situation improves, eventually work with.  If you work well together, push the pace and each don’t lead for too long, you might be able to eat back into the lead the group in front of you has and actually catch them.  Even if you were the thinnest line away from failure, if you can rest (not stop, but go easy or sit on a wash) for long enough you should have no problem finishing the race and going hard later on.  Remember completely hitting the wall is rarely, except in very long races, a question of energy but instead lactic acid management.

Managing lactate during a race

Here are some tips for managing your lactate during a race:

1. Go hard off the start/beach.  You have up to 10 to 15 seconds of free energy where you’ll produce no lactic acid because you’re using a different energy system (anaerobic-alactic).  

2. Then keep going really hard but understand that the clock is running.  Depending on how hard you’re going you’ve got from about 1 to 3 minutes before you crash.

3. Slowing down a little but still paddling at a pace you can’t hold for the entire race should get you a little further without getting into trouble.  A great training drill is to do 2 km time controls where you try to go as fast as you can for 2 km.  This will take anywhere from 11 to 15 minutes and will give you lots of opportunity to experiment with pacing and become familiar with managing your lactate levels.  It also roughly corresponds to the time or distance that the top groups often go hard for before they begin to settle into their traveling paces and draft trains.  

4. Get on a wash or slow down as the anaerobic clock is winding down and lactate is reaching dangerous levels.  If you can get on a wash you can maintain speed and, if you’re relaxed enough, you can start to work aerobically and stop producing lactic acid.  Over the next 10 minutes or so enough lactate will be removed from your blood stream to take you out of the danger zone and allow you to consider working anaerobically again.

5. Monitor blood lactate levels for the rest of the race.  Remember you no longer are operating from a zero lactate position.  You’re out of the danger zone but not by as much as you were before the start.  You’ll get back in danger much more quickly than you did initially.  Don’t be afraid to sprint when needed, but don’t be reckless.  Sprinting to stay in contact with the wash in a draft train is a good idea if required provided it doesn’t take too long, but you can’t go for an extended period of time.  At some point, if you can’t catch back up to the train you’ll have to let them go.  Remember wash represents your chance to rest while maintaining speed.

6. Know how much you have left at the finish and therefore where you can start your finishing kick.  Again, you probably can’t go anaerobic for a full 2 minutes at the finish as you’ll have lactate values that are higher than rest, particularly if you’ve done a few sprints during the race.  On the other hand, there is nothing to save yourself for.  The finish line is all you need to worry about.  If you seize up one stroke past the finish because of high blood lactate, who cares?  You’re finished.  In fact in this case you will have paced things perfectly.

7. Practice paddling at high intensity.  Producing lactate and working with high blood lactate teaches you a lot that you can use in your races, as well as improves your lactate resistance/tolerance.  And of course, learn from your races both in terms of what you did well and mistakes you made with regards to your management of lactic acid.  

Happy paddling and racing!