no idea but think this is a great question - looking forward to the repsonses.

Alright experts this is an excellent question and one that I also can't wait to hear the answer too. My races always seem to go out fast and then fizzle which I am trying to avoid and getting better at. But my training runs virtually always have negative splits. Which means I typically have fuel left in my tank when I finish the runs although I am running faster than when I started.

Bike rides are give and take and depend if it is solo or with a group.

According to Pfitzinger, "even" splits are the most effective way to reaching your potential. Over the longer distances that does translate into easier effort for the first half due to the demands of holding the pace.

I always try for negative splits in running races, but can only seem to do them in training. My running pb's have all been a result of hammering then surviving. In tri's I tend to stick with a specific pace/hr combo, for sure on the longer distances. In sprints I pound the bike and the run. I don't hammer real well in open water as I have this lovely tendancy to panic, so I stick with steady and smooth.

I run xc and track. Maybe it's just that i run shorter races (5k/3200m), but i almost always negative split my running races. During distance runs, i'll try to start out a little slower than my goal distance pace for the first 15 minutes just to warm up, but after that i usually hammer the rest of the run (generally 40-80 more minutes). During my running workouts, i'll try to simulate a race as much as possible and get some negative splits in there (during a 5 mile tempo, each mile gets faster by about 3-4 seconds). Whenever i race triathlons, i dont like to waste any energy that i have (especially because i mainly do olympic distance) on the bike. I still dont give it all that i have in the first 10 minutes of the bike so i burn out, but ill maintain a pretty steady pace throughout, maybe with the last 10-15 minutes going right at my lactate threshold. For the run, i use the same concept as in my running workouts. I'll negative split, but maybe on each mile by 2-3 seconds (because i'm going pretty fast already). I personally think that negative splitting is the way to go, but thats just how I feel. I'm sure everybody has their own style, which is why i wouldnt say that my way is the best way to go. I think its about finding your niche, because i'm sure that other people like going hard in the beginning or just maintaining a steady pace. Sorry for the Long response, Hope this helps!

Maximizing your potential in a race requires that ability to go both fast and far. Both capabilities need to be worked, but typically not in the same workout. That doesn't mean you might not try to put a little boost at the end of a long run, but more that the seriously high-end, speed focused workouts should be just that, while the aerobic building and endurance workouts should also be just that.

That article's authors' approach is to focus on the fast during the off-season. Rather than 3hr mind-numbing trainer workouts in your basement in January, their approach is to have you put in some painfully hard workouts that are shorter in length, but focusing on your high-end LT/pace/HR, adding the longer sessions once the weather warms up. But, I believe they also acknowledge that this works best if you've already got at least some aerobic base, ie. someone coming right off the couch might be better served building up a little bit of aerobic fitness before worrying about getting faster.

The more traditional approach over the course of a season (Joe Friel and others), focuses on developing a very solid aerobic base during the off-season, point being that if you don't have the endurance to do the distance, then it doesn't really matter if you can go fast for 15 or 20min. Focused speed workouts can then be added in the spring as you begin to ramp up for your first races of the season.

Two different approaches, both have shown effective results, and both have their critics. That doesn't mean that your speed sessions don't have recovery periods, or that your long runs or bike rides can't have 5 or 10min stretches at a harder effort. In a nutshell, I believe they should. But again, each workout should be understood to be focused on speed vs endurance, as it's typically unrealistic to improve both in a meaningful way at the same time.

During the race, going hard is a relative term. Simply put, your body has a limited supply of glycogen, and the harder you go, the less able it is to use fat as an energy source. Therefore when you hit that point at which your body is burning more glycogen than fat (your lactate threshold), you have a limited amount of time before you run out of gas, so to speak. As Gsal points out, in shorter distance races (5Ks, sprint tris), you can push at or even potentially above that lactate threshold for the entire distance, because you are likely to finish that race before running out of fuel. But the longer the distance, especially once you start to move beyond 90minutes, the more you may need to moderate your front-end effort if you don't want to be walking/shuffling that last mile or two.

RACES are negative split, or even pacing, depending on distance.

Workouts are never negative split unless specifically called for. You can mix up tempo and pacing, but you shouldnt be hauling butt home every workout.

[quote=Triguy98]RACES are negative split, or even pacing, depending on distance.

Workouts are never negative split unless specifically called for. You can mix up tempo and pacing, but you shouldnt be hauling butt home every workout. [/quote]

Exactly.

[quote=Triguy98]Workouts are never negative split unless specifically called for. You can mix up tempo and pacing, but you shouldnt be hauling butt home every workout. [/quote]

No, you shouldn't be hauling butt back home, but you shouldn't be dragging it either.

Intervals should always be done even or negative split, because the last ones are where your work really comes in. If you can't hold pace, you either started out too fast, or you're at the end of the workout. Same principle applies for long runs/rides. You should be able to finish at the same pace (though increased perceived effort) at the end as where you started, or even slightly faster, just as you would a race.

That said, my races all tend to be start out fast, hold on through the bike, and finish fast(-ish), but I was a swimmer/runner growing up. My running PR's, from 800m through 10k were always a positive split, but that was dictated by the pace of the race and staying with the lead pack.