How to Train Through Low Iron

It’s a depressingly common experience. Your workouts have become lackluster and you’re drifting into a training space in which nothing appears to be going well. At first, you think you’re tired, overstressed, and possibly overtrained. You do what you can to fix those, but you continue to drift. Then it dawns on you: maybe you have low iron.

You get a blood test (including ferritin, an early indicator of low iron), and yes, it is. You’re not clinically anemic, but your iron is suboptimal, especially for an endurance athlete.

Most runners associate iron with hemoglobin, the iron-containing molecule that helps red blood cells carry oxygen to your muscles. But it is also critical for the production of enzymes needed to convert the energy produced by aerobic metabolism into movement, says Katie Lucernoni, an exercise physiologist at the University of Oregon. “If you don’t have enough iron to make [these enzymes], you are essentially limiting how much energy you can make,” she says.

If that’s you, take heart on one thing: you’re not alone. Studies have found that perhaps 35 percent of female athletes and 10 percent of male athletes have found themselves in this situation at least once. For distance runners, the figures might be substantially higher, because running shortens the life of your red blood cells by about 25 percent, wearing them out in 90–100 days, rather than the 120-day life of the average couch potato’s underused red blood cells.

“Some studies have shown that in athletes running more than 40 miles per week, the life expectancy of red blood cells reduces to 70 days,” says USATF coaching instructor Scott Christensen.”

And while the body recycles most of the iron in an aging red blood cell, some inevitably escapes, which is a problem because you don’t have vast amounts to begin with. “You can get low rather quickly,” Christensen says.

How to Rebuild Your Iron

The first response should be to do what you must to restore your iron. If your diet allows, eat red meat. (I like to joke about eating blood sausage.)  Avoid mixing meat with cheese (whose calcium might impede absorbing iron). Take an iron supplement (along with vitamin C, which enhances iron absorption). But don’t pay too much attention to Internet hype over what’s the ideal supplement. “There is no ‘best’ iron supplement,” says Andrew Begley, coach of the Heartland Track Club, who has worked with multiple Olympic contenders with low iron. “There is the best one for you.” (I.e., you may need to experiment.)

But unless you resort to an intravenous iron infusion, restoring your iron takes time, and in the interim, you’re still drifting. So, what can you do to minimize the fallout, so you can come back strong and fit as quickly as possible after your iron rebounds?

The answer depends in part on just how far your reserves have fallen.

How to Train in the Meantime

If your iron is truly in the toilet, says Eugene, Oregon, coach Bob Williams, who has worked with everyone from beginners to pros, you may actually have to set aside your training shoes and get on the bike or in the pool—“some kind of activity where the aerobic demand is lower,” he says. “Then experiment and see how much you can do.” Tom Cotner, coach of Seattle’s Club Northwest, has runners switch to the bike, then gradually phase back into running, a few minutes at a time.

Whatever you do, resist the urge to try to power through as though there isn’t a problem. Not only is that a form of denial, but if a coach tried to make a trainee do that, Williams says, “they’d be abusing the athlete.”  Not to mention that it isn’t going to do you any good, and could easily add injury or overtraining on top of your existing low-iron problem.

Time for Something Completely Different

Besides reducing your aerobic training load, it’s also a good time to work on things you don’t normally do. All forms of athletic activity, Christiansen says, are based on five primary components: speed, strength, flexibility, coordination, and endurance. “It does not matter if you are a defensive end for the Rams or a distance runner,” he says. Distance runners are notorious for focusing almost entirely on endurance. Christiansen says, “They may say speed is important too, but the type of speed distance runners think is speed is just faster endurance work.”

Of these components, only one—endurance—is significantly affected by low iron. So, Christiansen says, “If iron deficiency knocks down your ability to do endurance work, it becomes the perfect opportunity to concentrate on the other four.”

When you think of it this way, the opportunities are wide open. Some options include:

• Coordination: Get an agility ladder and learn how to do drills on it. (A great instructional video can be found here.)
• Flexibility: You can find scores of effective dynamic stretching/warmup activities with names like high knees, butt kicks, carioca, and toy-soldier walk. They are fun to learn and practice, and great to keep in your routine once your iron returns to normal to build range of motion, posture, and explosiveness.

Or, you can try what Christensen calls “ground gymnastics” in which you do various forms of crawling: “bear,” “crab,” “gorilla,” “inchworm,” and “tabletop,” all in multiple directions, with the goal of building mobility, core and posterior-chain strength, and basically having fun. Keep individual crawls to 40 seconds, he says, and take 3-minute breaks between them.

• Strength. Hit the weight room and do small numbers of reps at relatively heavy weights. (Christiansen suggests 8 reps per set at 80 percent of one-rep max.) Or take up plyometrics, such as split lunges, body squats with a jump, or explosive step-ups. Again, keep the number of exercises, reps, and sets limited, with multi-minute breaks before repeating the same exercise.

• Speed. Do some really short, really fast sprints, with lots of recovery between. How short? One option Christiansen suggests are 60-meter reps on 3-minute walking recoveries, but his favorites are 30-meter flies, in which, after a run-up, you go very fast for 30 meters, then cruise to a halt. Recoveries are 3-4 minutes, walking, not running. Start with a handful of reps, and build up to eight—but don’t shortchange the recovery. You can also do a similar workout on a hill, either on pavement or grass. Plyometric-style skipping and hopping drills also increase both strength and sprint speed.

There are, of course, a few caveats:

• Make sure you do these exercises correctly. Find online videos, hire a trainer, or get a knowledgeable friend to watch you and give you tips.
• Start conservatively. Not only are you taking up new skills, but you are using untrained muscles. Give your body time to adapt.
• Don’t link these exercises into extended circuits. “Keep the individual efforts very short, with lots of in-session recovery,” Christensen says.

Normal—But Careful—Training

If, as is the case for most people who catch it early, your iron isn’t drastically sub-par, you may still be able to run, and even continue speed training. “I think you can still maintain fairly decent aerobic activity, as long as you’re starting to correct the [iron] problem,” Lucernoni says.

Not only will this reduce the degree to which you get out of shape while your iron is rebounding, but doing what you comfortably can is also good, psychologically. “[We] try to keep things as normal as possible,” Begley says. “This helps [athletes] feel like they are still doing the things they need to be doing, and it allows them to train with their teammates.”

That said, your training will need modifications.

The easiest part of your routine to maintain might be speedwork—not just the super-short sprints suggested Christiansen, but longer reps done at, say, mile race pace. “[These] intervals are short enough that low iron doesn’t have a huge impact,” Begley says. “If we do see an impact, we increase the rest time.” Exactly what length of interval you can do will depend in part on how fast you are.

My experience is that somewhere between 45 seconds and 60 seconds, the going starts getting tough, which means 400s, and even 300s, are likely to be too much for most people.  Begley agrees. “Quarters are about as long as athletes can go without changing the pace or rest,” he says.

“Start at 50 meters,” Williams recommends, “and recover for a minute or two. Then stretch to 75 meters, 150 meters, 200 meters—that sort of thing, to see what you can do.”

Steady-paced aerobic work, such as tempo runs may also be possible without too much modification other than slowing the pace to whatever feels normal. You can also break up a tempo run into shorter reps, on short recoveries. Jack Daniels, author of Daniels Running Formula, calls these “cruise intervals” and has noted that even with normal iron, they can be a very effective substitute for the classic 3-mile tempo run. My favorite is 600 repeats on 20–30 second recoveries, though with low iron you may need to lengthen the recovery. The key is to keep them slow enough that the first few feel easy. Eight reps is 3 miles.

Other types of speed work may need more modification. “It’s the in-between work that is affected the most,” Begley says, meaning longer intervals such as 800 meters to the mile, often run at the upper end of your aerobic capacity. “For [these],” he says, we typically slow the pace a bit and give more rest.”

Bottom line, do what you can do, and be patient. One of Begley’s trainees, Allie Wilson, started the year with low iron. She wound up in the Paris Olympics.