 Hey everybody, I'm Lance Goikey. Today I want to discuss the difference between a sprint and repeated sprints. So if we've talked about, if you've watched my video about warming up, this kind of ties into that really really well. So if I do one sprint, let's say it's 10 seconds long, I do that sprint for 10 seconds, a large percentage of my energy is gonna come from my alactic anaerobic energy system and that's how we understand those things. It's short. It's really intense. It's got to use the fastest way to create energy. Now if I do four of those, my first one is gonna look like we just said a lot of ATP-CP, a lot of alactic anaerobic energy development, but as I get to the fourth one, I'm gonna start getting more and more tired and I'm gonna start running out of creatine, which has phosphate on it, and I'm gonna have a smaller pool of energy of creatine phosphate to use for my alactic anaerobic energy system. So if, you know, let's say, for example, 75% of my energy from that first sprint came from that alactic anaerobic energy system, then maybe it's like 50% on my fourth sprint of 10 seconds, as long as I'm getting, you know, 60 seconds of rest between each round. If I take only, if I go a 10-second sprint, but I take only 10 seconds to rest, then by the fourth one, it's gonna be much, much more aerobic and much more lactic anaerobic because I'm not allowing time for that creatine phosphate to replenish itself, and that's the only thing that's needed for that alactic anaerobic energy system. Now, if we think about it, maybe a little bit differently, let's go through just another example. Let's say we're doing a 30-second sprint, so a lot longer. This feels much more glycolytic. This feels much more lactic anaerobic, is another way to say it. For the first 10 seconds of that first sprint, I'm probably getting a lot from my alactic anaerobic energy system, then it runs out of that creatine phosphate. It can't do that anymore. That's when the lactic anaerobic system kicks on. That's when I start to take that pyruvate from the glycolysis and make more lactate, if you know any of your biochemistry. And that's what keeps my glycolysis going. It's fast, but it's really inefficient. So it doesn't make a whole lot of energy, and it runs out of the ability to do that pretty, pretty quickly. Maybe about 30 seconds, depending on how hard you're going. Maybe up to two minutes. If you're not going that hard, but you are going above a level that you could maintain. Now, if I do that, and maybe I do my 30-second sprint, we've described how the energy comes from that, right? The first 10 seconds is very alactic anaerobic, and then the final 20 seconds of that sprint is going to be very lactic anaerobic. Now, if I do six of those, and I rest two minutes between each one, then by the end of that, I'm starting to run out of phosphorylated creatine, that creatine phosphate, that thing that I need for the only step of alactic anaerobic energy development. And I'm starting to build up more and more lactate in the blood. And so I have this, this like, hey, stop, we have enough kind of effect going on. And so my glycolysis has to be more and more aerobic. So if, you know, maybe the first five seconds of my sprint now has come from my alactic anaerobic system, and then maybe the next 15 seconds is primarily from my lactic anaerobic system. This is just a simplification to see it and to understand it. But the point being, my aerobic system is now going to take more of the brunt of the energy development, because not only are the other two systems being more exhausted, but my alac, or my anaerobics, stop it. My aerobic system has now had time to get going by the time we're on our sixth repetition of this repeated sprint, sprint over and over. So 30 second sprint, two minute rest, six times. By the sixth time, my aerobic system is definitely going a lot more than it was going on my first one, even if I warmed up. So that is, I mean, that is the characteristic that really describes the difference between normal sprints and repeated sprints. Now most activity is repeated sprints. So unless you're a shop putter or a hammer thrower or a long jumper, whatever, you need to maximize that sprint sprint. But if you're a team sport athlete, you play football, soccer, hockey, any of those kinds of things, basketball, then I need the ability to keep close to my peak sprint for as long as possible. So on that sixth, on that seventh, on that 70th sprint, I still have my energy production capabilities. I haven't gassed out and I can make a lot of energy through the aerobic system. So that is just the major difference between a sprint and a repeated sprint.