You've been putting in good mileage, you want to go faster, you've already watched my video on steady state training and you think, all right, time to pick up the pace. What else can I do? Well, I'm Jesse Funk. And today on this episode of Runners High, we're going to talk about threshold training and what that means. What's the difference between aerobic threshold, lactate threshold, anaerobic threshold? Is there a difference? What does it all mean?
So, what do I mean when I say threshold? What I mean by threshold, what another coach means by threshold, maybe a little bit different. But rest assured, there are two main zones when we're talking about threshold. To add to the confusion, like I mentioned in the steady state training video, some people refer to the longer version of threshold work as tempo.
So, keep in mind that you need to know a little bit about what intensity is a particular coach asking you to go at. And sometimes you can measure that in a matter of heart rate or percentage of heart rate, and figure out okay, that's what they're asking me for.
When I refer to threshold, I'm actually referring to lactate threshold, which we'll get to in a minute. But first, I actually want to talk about aerobic threshold. Aerobic threshold is one of the two threshold zones. I personally will never refer to this zone as threshold. It's actually similar in effort to sweet spot training. It's the effort where your body is still using almost entirely aerobic capacities.
The point where you're still burning predominantly fat as fuel, and getting ready to change over to using more glycogen from your muscles to produce energy. So, that's the threshold.
And what makes sense when we're using this word, threshold for all these different things is typically, we're talking about an area where your body is going to start beginning to burn fuel in a different way. Moving from fat to glycogen or glycogen in an aerobic capacity to an anaerobic capacity. So, that word threshold, really has to do with this line of demarcation in, you know, where we're changing the source of our fuel.
Now, what I actually refer to as threshold can be interchangeably mixed with two different terms; anaerobic threshold and lactate threshold. Scientifically, there is ways to measure a difference between anaerobic threshold and lactate threshold. But a lot of people use these terms interchangeably.
And we're talking about this similar same kind of zone where your body is moving from an aerobic state and then crossing over that threshold, that line of demarcation into a state where you're in using an aerobic process to produce energy and producing lactic acid.
Now, I personally, and this is something-- all of these terms I picked up from coaches through the years and adopted them myself. I refer to the lower part of this zone because again, it's a gradation, not just a strict line of demarcation. I refer to this lower part of the zone as lactate threshold.
And the reason I do that is because on the lower end of the zone, you're typically going to have some kind of longer interval where you're building up lactate in your muscles through a gradual period of time. Versus the higher end of the zone, I just simply call threshold because it's more often associated, at least with the things that I create for schedules, with shorter intervals on the track, anywhere from a mile on down.
So, those are my particular terms, but what can we do with this zone? How do we define it and how is it useful for you? So, like I said, this zone is where your body is starting to produce lactic acid, just slightly faster than it can clear away from your system.
And without going to the lab and doing blood testing to figure out the lactate levels in your blood. You know, how do you know that you're actually in this zone? As a good rule of thumb, you know that you're in this threshold zone when you're at 70 to 85% of your max heart rate.
If you watch my heart rate training video, I actually share a tip where if you don't have any heart rate equipment, which I don't any longer because I lost the piece I needed with my watch. I still use heart rate by using this trick of counting my heart rate for 10 seconds.
Two fingers up to the vein in your neck, and you count your heart rate for 10 seconds. So, what does that translate to? Personally, I have a max heart rate of around 200 beats per minute. So, for me, the 70 to 85% range is from 23 beats per 10 seconds to 28 beats per 10 seconds. And that helps guide me when I'm doing these workouts.
Like I said earlier, the lactate threshold workout or what I refer to as like a threshold, where I'm maybe I'm going on that 70% end for like 20 minutes, I know that I want to be hitting like 23, maybe 24 beats per minute, you know, at the end of that workout, then I know that I have the correct effort. Whereas if I want to be on the high end, that I know 27-28, maybe 29 beats per minute, that's about all I want to maintain.
The whole point of doing this kind of training is actually to train your body systems to clear lactic acid out of your muscles more efficiently. This means that you can work at a higher intensity without accumulating that lactic acid, which will eventually cripple your muscles ability to function.
So, if I was going to start you out in this kind of training might start you with maybe like a 20 minute run at 70% of your max heart rate. We're starting in the lower end and trying to accumulate lactic acid over time. This intensity is a good starting point to figure out okay, am I fit enough for this kind of workout, and then where do we go from here?
Another way to approach it might be 10-minute intervals with a very short period of rest Let’s say 10 minutes at that 70% and then you take one, maybe two minutes of walking rest and then another 10 minutes. That can be a better way to jump into it if you're not quite ready for that 20-minute interval.
As you gain fitness, you may start working towards the upper end of this threshold zone, what I typically refer to as threshold. And that's actually going to be the meat and potatoes of what you need to put together a really fast 5K pace. One of my favorite workouts for working on this zone is 1,000 meter repeats with about 90 seconds walking rest.
The difference between that lower end around the 70% max heart rate and moving towards the upper end, around 85% of your max heart rate is that you're going to produce lactic acid at a higher rate, which makes sense, right? You're working harder, you're going to produce more lactic acid.
Which is why you have to have shorter intervals. So, 1,000 meters instead of you know, a couple miles maybe with that 20-minute interval. And then you have the walking rest, which gives your body the time to clear out the lactic acid while you're not producing more through running and gives you a chance to try to work at a higher rate, while also dealing with the fatigue and accumulation of lactic acid.
So that's the short of it, threshold. It's a lot of what you're going to do if you're working on 5K, even 10K pace. If you're a marathoner or half marathoner, you may do it occasionally, but it's not going to be as useful for you. In the last part of this three-part series, I'm going to talk about what I often refer to as just interval work or rep pace, two separate pieces that are above this zone of threshold.
The video should be popping up right next to me. Click on that to see the last video. Don't forget to subscribe. I'll see you next time on the next episode of Runners High.