Former Redskins' linebackers coach Lou Spanos has a word with linebacker London Fletcher during Day 9 of Redskins training camp in August. (John McDonnell/THE WASHINGTON POST)

Let’s say your job is to take off at a sprint, get moving about 20 mph and slam yourself full speed into a brick wall — 60 times in a single afternoon. We’d give you a helmet and lots of padding to protect yourself. Because of the toll this would take on your body, we’d make you do it only once a week. And we’d reward you handsomely.

One other thing. While you’re flinging yourself at that wall, other guys would be plowing into you at roughly the same speed. From all angles. They might hit you in the legs, the chest, the head — pretty much anywhere except from behind, with similar force.

That really doesn’t exaggerate what Redskins linebacker London Fletcher does for a living. Yet Fletcher, 36, has not missed a single game in his remarkable 14-year career. That’s 224 consecutive regular-season games at one of the most violent positions on a football field. And this past season, Fletcher, one of the oldest players in the league, led the NFL in tackles.

Most NFL careers last just four to six years, depending on whether you believe statistics from the players union or the league, and nearly everyone who plays any length of time misses a game sooner or later because of injury.

Not Fletcher. With the Super Bowl approaching, I thought I’d ask him what he does to prepare himself for the mayhem he faces on the field each week, and how he has managed such longevity. There are fitness lessons in his replies for those of us who only hold a remote and watch Fletcher do his stuff.

How have you managed this kind of streak? Does it have anything to do with your fitness regimen?

Yes, definitely. In the offseason, I work out maybe four or five times a week, weightlifting, and then also speed work, cardio work, things like that. I do strength [training], elliptical machines.

Once the season starts, I work out two to three times a week and then also . . . massages twice a week . . . active release therapy, I do that. I do acupuncture. . . . Nutrition is also big, and then rest. . . . I also have been blessed with great genes. God gave me great genes.

Can you take us through an offseason workout day?

Monday, I may get up, lift weights, then go to the field. Depending on whether I’m doing an upper-body lift or a lower-body lift, that’ll determine what kind of run work I may do. If it’s an upper-body lift, then I can do a little bit harder running-wise, with my sprint work or my resistance cord work that I do. I do hills, do a little hill training as well.

If you’re doing sprints, how many and for how long?

It might be 14 40s [40 yards], 16 110s or 120s. It could be 10 sprints with a resistance cord. It just kind of varies. I also may do some position work, where I’m doing my linebacker-type movements in a time period, in sets of 10.

Do you do any distance work?

Nah, I’m not built for distance. I’m built for sprints. I’ll do maybe a 30-minute elliptical, that’s what I’ll do from a cardio, endurance-type standpoint. I like to get the heart rate up and keep the heart rate up pretty high. . . . It can get up to 160, 170.

At one of the roughest positions on the field, you’ve never missed a game due to injury. Have you ever thought what the reason for that is?

I think I got a great deal of toughness. As I mentioned before, just being blessed with great genes. . . . I’ve been fortunate not to have an injury that would not allow me to play. If I have injuries, I’ll get as much treatment as possible to try to give myself the best chance to play.

How much strength training do you do?

I do that probably four, five times a week. . . . Anywhere from an hour, an hour and a half of strength training. Upper and lower body. Then you got your core work that you do as well. I do a little bit of yoga as well.

Is that for flexibility?

Yes. . . . I may throw in a little Pilates this year. Lorenzo [Alexander, another Redskins linebacker] told me about Pilates. He likes it. So I may try it.

In a given week, how much time do you devote to working out?

You’re looking at probably about 20 hours a week, 20 to 25 hours a week.

Do you do anything special toward the end of the season, when you have all those bumps and bruises?

Getting in the cold tub, hot tub . . . hot-cold contrast. Deep-tissue massages. Steam room. Those types of things. . . . I get in the steam room during the offseason as well.

What would you say is the most important part [of your fitness regimen]?

Being in the best possible shape, first and foremost, to give yourself a chance to compete at the highest level. Then from there, staying on top of detail, attention to detail. Always challenging yourself to get better. Never becoming satisfied or complacent in what you’ve accomplished. I’ll always look to see how I can improve in the offseason in particular. Just trying to see, “Okay, I want to do this to get better, get stronger, get faster.”

How would you compare yourself to when you broke into the league?

I’m smarter. I’m stronger. I have a routine. I know how to prepare myself for the grueling season. . . . Now I have a plan, and I know how to execute my plan.