As many of you will remember, in the three weeks before the Chicago marathon I was feeling overtrained. I wasn’t sleeping very well, my heart rate would spike upon doing any sort of activity (including climbing one flight of stairs…), and most notably, my legs felt “flat.” When I say my legs felt flat, what I mean is that they had no power or zip, and suddenly paces that once were a breeze started to really tax me. Did I mention I was moody and cold all the time, too?
Most of these are all classic symptoms of overtraining, and since I slipped in a few high mileage weeks along with a few speed sessions, I concluded that I must have overtrained. The most frustrating thing about this though was that on most of those days when I ran faster, I was doing so because it felt good; I wasn’t pushing myself to go fast just for the sake of it, it just sort of happened, which seemed like it meant I was simply fit enough to have lowered my average normal pace. With this in mind, it didn’t make complete sense that I would have had most of my runs feel good and then all of sudden land myself in an overtraining situation.
Well, I have a new theory to explain what I felt in those pre-Chicago weeks.
First, recall from this post that overtraining occurs because of a lack of rest between hard efforts, not because of the hard efforts themselves. How much rest a person needs between tough workouts is a highly individual matter, but even with an individual person it can be tricky to exactly determine the right balance of hard workouts (which build strength and fitness) and rest (which repairs muscles and prepares them for the next workout). This balance of work/rest depends on usual factors like genetics and running experience, but it can also depend on your dietary health at the moment. Let me explain.
As you know, proteins, fats, carbohydrates, vitamins, and minerals are all needed by the body in certain amounts, and the body uses these assorted things in varied, distinct ways. For example, protein can be used to build muscle fibers and/or to make hemoglobin (the part of a red blood cell that carries oxygen throughout the body), and folate, or folic acid, can be used to produce DNA (say, for new cell production). Many essential compounds can be synthesized by the body “in house,” but many can’t; to get those essential compounds not created in the body, we rely on our diets.
Here’s where the notion of health “at the moment” enters. For most people, whether or not you have enough of a certain vitamin or mineral is not a genetic matter – it is a dietary one – and one that can really change drastically in just a few weeks. Since proteins, fats, carbohydrates, vitamins, and minerals play important roles in processes like muscle repair and red blood cell production, a deficiency in any of these compounds will likely be reflected in your training. Such deficiencies can arise rather suddenly, so it’s possible to be going along with training and feeling great, and then all of a sudden start feeling ‘off’.
This is exactly what I *now* believe happened to me back in September, just weeks before Chicago.
In July, I started taking an iron supplement* because I knew female runners ran a higher-than-average risk of becoming iron deficient, and I was anticipating the requisite mileage-volume-increase that came with marathon training. Also, iron is one of those elements that the body does not produce on its own, so it’s necessary to get it from diet. I was great about taking this supplement for a few weeks, and then for absolutely no reason at all, I just kind of stopped. For a few weeks nothing happened and training progressed really well (this was around mid- to late August); then in early September, Lina and I ran our second 20 miler and it was around that time that things started to decline. Two-thirds of the way through September, this is what I experienced:
-I started having trouble keeping an 8:45 pace (normally a nice cruise pace)
-My heart raced every time I stood up
-My hair fell out
-I was intolerant to cold (i.e. cold all the time)
-I woke up a lot at night, and always felt tired even when I got 8 hours of sleep
-I was moody and depressed
-I couldn’t focus
-My legs were always tight
-I craved caffeine like crazy
These are all classic symptoms of overtraining, and I still think I was overtrained. BUT, I wasn’t overtrained because I truly ran too much and rested too little; I was overtrained because suddenly, my body wasn’t recovering enough during the rest periods. That is, I was giving myself the same amount of rest in September that I had given myself in June and August, but in June and August this amount of rest was sufficient and in September it wasn’t. I now believe that I ceased to adequately recover in September because of an iron deficiency.
This brings up the question of the role iron plays in recovery. Iron aids in recovery because it is intimately involved in red blood cell production, and red blood cells carry oxygen and carbon dioxide throughout the body. To quote from the American Red Cross website, “Inadequate oxygen supply to tissues results in poor healing of tissue and can cause complications such as an increased workload on the heart.” Considering that distance runners tax their muscles and lungs as part of the territory of the sport, it’s no wonder that an iron deficiency (which leads to fewer red blood cells and poorer circulation of oxygen) can greatly impact performance.
As a distance runner, you can land yourself in an iron-deficient state in a few different ways:
1) Foot Strike Hemolysis: Red blood cells get crushed with every step we take, so by multiplying our number of steps with high mileage and increasing the force with which we step by running (versus walking), we distance runners murder a lot of red blood cells. The incredible thing about the human body is that it is so adaptable, so given the proper nutrients, our bone marrow will rise to the occasion and increase red blood cell production to compensate for all those that are lost.
2) Sweat and Urine: Small amounts of iron can be found in sweat and urine, which doesn’t present a problem until those hot summer months. Very fit athletes have been shown to start sweating sooner than less fit individuals, and some people (like ME) produce a higher volume of sweat than others due to genetics, which means that in hot, humid conditions day in and day out, athletes, sweat monsters, and athlete sweat monsters can actually lose a notable amount of iron.
3) High Carbohydrate Diet: A diet high in carbohydrates alone won’t disrupt the balance of iron in the body, but most people will simultaneously decrease meat consumption when they increase carb consumption, which will land them in a situation where not enough iron is taken in. There are two main types of iron, Heme and Non-Heme, and Heme iron is much more easily absorbed by the body. But, Heme iron is only found naturally in animal products. It’s possible to get enough Non-Heme iron through foods like dark leafy greens and legumes, but it’s much more difficult so extra care has to be taken.
Additionally, if you are a woman you will also lose iron and red blood cells during menstruation each month. We all took health class or sex ed or whatever they call it, so I won’t elaborate.
In any case, it’s easy to see how I, a super sweaty, female marathoner, could be at risk for becoming deficient in this extremely important element. Iron is also a finicky thing in terms of absorption, which only makes matters worse. Calcium, for example, inhibits iron absorption. Of course, calcium is also vital for bone health (again, especially for women) so you have to get enough of both…somehow. Caffeine discourages iron absorption as well. Without realizing it, I was caught in a cycle of destruction because I was tired from not getting enough iron, so I drank a lot more coffee, which then prevented me from increasing the amount of iron I had in my body, which made me more tired.
I started taking the iron supplement again around September 25th, and by the time Chicago rolled around, most of my symptoms had vanished and I had apparently restored my iron supplies enough to make it through the race. I ran out of the iron pills the day of the race, though, so by the end of October, I started to see the symptoms return. I was running significantly less since I was no longer training for a marathon, so I was baffled. It was only from scouring the internet that I realized that iron may be to blame for how I felt and not true overtraining.
I have since started the iron supplement again and I feel like a new person, which is why I think I have finally figured this all out. This journey has made me want to pay much closer attention to my diet, not in the sense that I plan to restrict myself in any way, but in the sense that I need to make sure I’m getting enough of everything I need nutrient-wise, not just calorie-wise. It has also made me accept the fact that I may need to make iron supplements a permanent part of my life, and it has made me realize that there are a lot more factors to consider than just miles and speed when it comes to how I’m feeling as a runner.
*Be careful with iron supplements. Iron toxicity (iron poisoning) is bad news and presents, ironically, with very similar symptoms to iron deficiency. So be modest with your dosing if you decide to take an iron supplement!