1. Start too fast: This will hurt you in shorter races, kill you in longer races and destroy you in the marathon (on my imaginary rating scale, kill isn't as bad as destroyed. Would you rather be killed by something or absolutely destroyed?) When I was coaching high school, I would tell my kids that they can either run the second half of a race as hungry lions or dying gazelles. The later stages of a race is painful enough. Being in a lot of pain while constantly being passed will steal your racing soul. If I'm going to be dying, I'd rather pass a few people in the process. Nearly every world record in the distance events was set by running negative splits (the second half being run faster than the first), so relax in the beginning, find your rhythm in the middle and THEN go for scalps at the end.
2. Make all runs medium runs: I see this flaw used the most by newer and lower mileage runners. Rather than hitting up a variety of paces, nearly every run is the same pace, regardless if it's a short run, longer run or race. Yeah, they may build some race-specific fitness, but they don't recover well, can't get their mileage high enough and more often than not, fail to hit their racing goals. The most efficient way to train, regardless of speed or experience is one that sprinkles in a variety of paces nearly all year long. Marathoners need 5k pace workouts, to match their long, glycogen-depleting runs and 5k runners need the long, mentally-tiring tempo runs to go along with their down-and-dirty speed work. If you're at a point where your daily and long runs aren't that far off your marathon pace, lower the speed a bit and increase the volume.
3. Neglect Speed: Wow, this is a nice follow-up to #2. I think this applies much more to older runners than the young, fast bucks (on another note, the rapper, Young Buck lived a few miles away from me and on the same street as two runners I know. After the IRS came down on him, he left behind all this sweet stuff, including this two concrete lions on his porch that I really had my eye on. Unfortunately, they were confiscated.) But yeah, don't neglect speed. For the marthoners, being fast a few months out from your goal marathon will help you develop your aerobic engine and make the transition to marathon pace feel easier. In college, I would never do anything "fast" until the racing season started. Once I started speedwork, I would get beat up really quickly, followed by an early peak, which usually proceeded injury. Now, I stay somewhat fast nearly all year, and do a lot more speedwork as a marathoner than I did as a 5k guy. But I think one of the biggest benefits to speedwork isn't physical, but mental. Running fast and hard HURTS. I find the speedwork pain makes you learn to hurt more in races and makes you mentally tougher and racing mean. Sometimes newer runners get used to #2 on this list and never get out of their comfort zone. With newer runners I coach, I usually give them a little more speedwork earlier onthan I typically give the more experienced ones to teach them to hurt and more importantly, that they can run FAST when they grit their teeth and make themselves.
4. Recover Inadequately: This is a killer for a lot of people here. If you can't recover, you can't adapt to all of your hard training and get faster. I've always compared not recovering well as someone who doesn't sleep very much. Yeah, you'll accomplish more in a 20 hour day than a 16 hour one but eventually, you'll crash later and accomplish less in the long run. It's sort of like a terrible example of the tortoise and the hare. I can't count the number of times I've heard an elite athlete reflect on their career and state they wish they would have taken their easier days easier. Other than workouts and long runs, I will typically run my easier runs around 6:50 pace. Sometimes I go faster (but very rarely faster than 6:30) and sometimes go north of 7:00. My shorter runs of the day have a much larger range and are usually anywhere from 7:00-7:45 pace. In college, when my training log was an unpublished book titled "Overtraining for Dummies", I would run my easier runs closer to 6:00. But I will admit that I found that with lower mileage, and lower intensity (when just starting training after resuming a break usually), my easy runs pace really speeds up because I'm more "day-to-day fresh". But this only lasts a while and disappears when I ramp up my training. I think elite marathoner, Camille Herron said it best when she stated that she can tell she's getting in shape and training hard when her easy days become SLOWER (that's my ghetto version paraphrase). So for the 90% of people who are probably guilty of this, slow down your easy days a bit, speed up your hard days a bit and race more than a bit faster.
5. Overtrain: Man, these mistakes really build-upon each other! As mentioned earlier, I was a poster-child for this while in college. I ran workouts in college that I probably couldn't touch now and as a result, I usually raced times that I don't touch now (because I'm faster). I don't need to write much here because I believe this is connected to #4 quite a bit. But I will state that if you want to see how fast and how far you can go, you have to train harder and as a result, sometimes overtrain. If you want to take it to the edge, sometimes you fall off. It's just part of the game. But rather than shoot for the cliched "110%" shoot for 95-100. You'll be waiting for those overly optimistic people at the finish line.
6. Indulge in all you can eat workouts: I try to stay away from all-you-can-eat places because I feel like I have to eat, well, all I can. If I pay $5 for a pizza buffet and only eat two plates worth of pizza, I'm paying $2.50 a plate. But if I eat five plates, then I'm only paying a $1 per plate....much better deal! In college, I frequently also dined on all you can eat workouts. Workout times weren't times, they were bare minimums and I tried to leave everything on the track (or the rice fields). If I had 4x1 mile in 4:50, I would try and crack all under 4:40. The worst were the fast, intense workouts at mile pace or faster. I found that I could recover really quickly between reps and be ready to hammer again. So instead of getting wobbly legs towards the end of a 12x300m session, I was already feeling the pain by eight and continued to slam on the gas. Workouts weren't workouts, but a series of intense races. And at the time, I talked about overacing was bad but I was doing it 2-3 times a week. Go figure. Now, I run nearly all of my workouts in a progressive fashion. I ease into the first few reps, find my sweet-spot and finish strongly but always keeping the reigns on. I very rarely go "all-out" in workouts and based of my results, I'm having much more success with it. That's not to mean you shouldn't see what you can throw down from time-to-time, but the goal should be to hit your times/goals/distances while remaining strong and confident. Save the racing for races. If you're always pushing the edge, you'll eventually fall off.
7. Refuse to adjust workouts: This is a really tricky one, especially if you have a coach or are following a training plan from a book, etc. I used to never drop out of workouts and now, I do it every once in a while. Some may look at it as giving up or punking out, but over the years, I've really learned how to read my body and know what it needs. If I can't accomplish the goal of the workout or have already achieved it, I stop. If I feel like it's within reach and I haven't reached the stimulus I want yet, I speed up or extend it. When studying the theories of Arthur Lydiard, I used to think it was crazy that he suggested you not give a set number of reps for track workouts. He felt you should watch your athlete run and call the workout when you see fit. The concrete-sequential side of me had a lot of problems with that, but now, I know it's the best way. If you're feeling a too rundown and you have a hard workout scheduled, get a good warm-up in and see how you feel. Many times, you'll end up breaking the cobwebs and are able to surprise yourself. But if it just isn't happening, go for an easy run with some strides and try again the next day. If you are dying in the workout, there's nothing wrong with slowing down the pace or shortening the interval. And if it's windy, hot, humid, etc, you definitely need to adjust the pace.
8. Search for the Perfect Workout: Spoiler alert, it doesn't exist. The article talks about how some runners will take the workouts of several coaches and combinig into a hybrid program. Frankly, the doesn't work. It's like taking all of your favorite foods in the kitchen, combining them into a blender and expecting it to come out tasting better than a Zaxbys birthday cake shake. As much as I want chocolate cheerios, sweet onion Triscuits, raw honey and hamburgers to make a delcious smoothie, it's just not going to happen. No one good workout makes you a good runner, it's the cummlative total of all of them.
9. Become running fundamentalists: As someone said (I think), "if you want the same results, do the same thing." Once you adapt to them, the workouts you used to do no longer create the same stimulus. Sure, a six mile tempo run at 5:20 pace used to be pretty tough and helped you break 70 mnutes for the half, but if you're a 68:00 guy now, a tempo run at 5:20 pace isn't going to help you very much anymore. It's important to always add something new: more reps at a certain pace, keeping the same distance but speeding it up, etc. When I started my "comeback" about 4.5 years ago, I was very patient with things. As I became more fit, I slowly sprinkled in some new things. Now, I'm at a point where I can train pretty much in my "ideal" fashion. Yeah, I thought longer runs at 95% of marathon pace was a good workout three years ago, but I knew I wasn't ready for it. Make new changes over time as you adapt to your current stuff. And just because something doesn't work once, it doesn't mean it won't work the second or third time.
10. Delay Injury Prevention Plans: I need to look in the mirror here. This is one of the things I know I should do but have trouble finding motivation to do it. All of my injuries happen on my right side, most likely due to a weak gluteus medius. I push less weight with that leg and I can't do a one-legged squat on it without having my knee buckle inward. It also is the result of my overpronation on that foot. In the lower body, a weakness somewhere can cause an injury somewhere else down the kinetic chain. If you have obvious muscle balances, you need to fix them. If you aren't sure, seek out a knowledgeable PT who does muscle testing or get a real gait analysis done (having someone in your local running store watch you run doesn't count). I have an analysis scheduled for Friday afternoon, so I'll be interested to see what is found. But preventing injury isn't always about strength training. Make sure you recover well in between hard sessions, ease into increased stress slowly and don't be afraid to back off when its needed. But back to muscle stuff. Check out Jay Johnson's page for some excellent running-specific strength training, especially the lunge matrix and Myrtle Routine.
11. Train at Goal Pace: I see this one a lot and it usually results in overtraining and crushed dreams and egos. As much as you want to be or think you are a certain speed, you're not at that level until you get there. A 1:20 half-marathoner who trains like a 1:15 guy may run 1:25 on race and then is scratching his head (or hers) wondering what happened. And just because you have run a certain time in the past doesn't mean you can run that time now. Fresh out of college guys are kings of this. They may have been able to do tempo runs at 5:20 pace in college when they were running 90-100 miles a week but a year out of college, life happens, they become busy and lose a lot of fitness. But there they are trying to run 5:20 pace for tempo runs and wondering why they are having so much trouble. Run at your current level, let the fitness come to you and don't force things.
12. Race Stupidly. You've trained for months for your goal race. You've put in the miles, the hard workouts, went to bed early and have your weight where it needs to be. All of those things took countless hours of mental and physical work. And when race day comes, rather than executing how you trained and visualized, you pee it down the train and race like an idiot. Stick to what you know, what you practiced and what you've prepared for. That means going into the race well rested, getting consistent, good sleep the nights leading up to it and following a warm-up routine that you are comfortable with and is effective. There's no magic in race day.