This is an article I originally wrote for Spartan last year. Even if you aren’t headed to train in high altitude, inadequate blood volume can really make training more challenging. Enjoy the read and remember, you can always learn something!
My favorite quote has been written on my whiteboard for years now, and it goes like this: “Every time you go to bed late, sleep in, skip a workout, or ignore your diet, you improve my chances of beating you.”
In training, as in life, our focus, goals, and knowledge change over time. When I first read this quote, I was new to fitness. So I used it as a reminder to get as close to 8 hours of sleep as I could, try to get in more AM workouts, and focus on more nutritious foods.
Fast forward a few years to when I found Spartan Race, and once again this quote took on new meaning. Most recently, with my qualification to the Spartan World Championships in Tahoe, I’ve taken a deeper look into improved performance nutrition and new “obstacles” that may lie ahead. More specifically, I was worried about the possible effects that Squaw Valley’s higher altitude would have on my performance.
There are many articles, podcasts, and books you can read regarding high-altitude training. But I’m a dietitian, so my interest has revolved around the potential use of nutrition for elevation prep. Specifically, I’m curious about the decrease in blood volume that may occur when I leave my daily training altitude in Maine and head out to the higher elevation of Squaw Valley, CA.
Why blood volume? Because blood volume is related to iron, which is supported by the foods we eat.
What better place to start educating myself about altitude training than in our own Spartan Community. Racing at Altitude: What You Need to Know by Dr. Jeff Godin helped build a platform of knowledge for me. (In the article, he reviews the short and long term physiological responses to high altitude exposure. One of these effects is hypoxia, defined as the deficiency of oxygen reaching the tissue. Again, for more on this, read the article. You won’t regret it.)
But let’s look at how the right nutrition focus can put you in the best possible place to maximize blood volume. By doing so we give the body the best possible platform even when hypoxia is a risk.
Using Nutrition to Optimize Blood Volume
As we prepare for race day, we never know the true distance of the race, what obstacles we will encounter, and in what order they will be set. No problem, right? We train weekly to optimize all factors of the course, potential climbs and distances, and obstacle proficiency.
In the same way that this approach helps you prepare, you can do the same in your nutrition as you prep for high altitude. How? By eating enough of the right foods to ensure adequate blood volume for race day.
Think about it. Dr. Godin’s article speaks to the fact that a lower oxygen pressure gradient between the atmosphere and the body will lead to a reduction in the movement of oxygen into the body. Due to the reduced pressure gradient and lower level of saturated oxygen, we have less oxygen for the exercising muscle and a lowered capacity for aerobic exercise (Godin, 2015). Now, if we combine that with inadequate blood volume before we even arrive for the race, we are placing ourselves even further behind the eight ball.
The Key: Iron
Let’s refresh ourselves on the role of iron. Iron is a part of the red blood cells and assists in delivering oxygen to working tissue (read: muscle) as well as assist with actions within the body for the transfer of energy metabolism (Benardot, 2006).
Inadequate levels of iron in the body can result in decreased blood flow, delivering less oxygen to the muscles, and a resulting decrease in performance not only during a race, but throughout training sessions as well. It can manifest itself with feelings of fatigue on exertion and reduced muscle power.
Spartans have a demanding training schedule, typically with longer duration, higher intensity, larger workload, and hopefully a proper nutrition plan to support it. How do these factors affect iron levels? Here are a few examples:
- Dilutional Pseudoanemia (aka Sports Anemia or Athletic Anemia) — the rise in blood volume and red blood cells that can occur when an athlete begins an intensive exercise program. Because the rise in blood volume increases faster than the increase of red blood cells, it appears as though the athlete has anemia. However, over time, the body adapts and the concentration returns to normal (Benardot, 2006).
- Foot-strike Anemia — the breaking of capillaries in the foot as we get in our demanding runs. The breakdown occurs faster than the body can repair them.
- Restrictive Diets — Between work, training, and daily life, it can sometimes be easiest to have a very simple menu from week to week. However, you need to plan for iron-rich foods. Since only a small percentage of iron from food is absorbed, the recommended range is set high. (Coffee or tea drinker? You may be absorbing even less. More on that later.)
- Unbalanced Diets — Focusing on iron already? What about magnesium, zinc, folate, and B12? These vitamins and minerals assist the body in red blood cell production and help iron to do its job.
For the Ladies
If the menstrual cycle overlaps a race, you’ve got yet another obstacle to overcome — but not just for obvious reasons. Blood loss through menstruation also affects overall blood volume. This is another reason to focus on nutrition.
- Enough on cause and effect. Let’s talk solutions.
Here is how much iron you need to ingest, according to your sex:
- Males: 16.3–18.2mg/day
- Females: 12.6–13.5mg/day
Know the best sources.
You likely know that red meats and leafy greens contain iron, but don’t forget dates, raisins, beans, tofu, molasses, pork loin, shrimp, and fortified cereals.
All of these foods are good sources of iron as well:
- Beef Liver
- Bison Meat
Many ready-to-eat breakfast cereals are fortified with iron, and some fruits and vegetables contain iron, too (Clark, 1997).
Coffee addict? Tea drinker? Components of these drinks can inhibit iron absorption. There’s no need to give them up; just try to separate food intake from coffee or tea by at least an hour.
Read the full article by checking out this link: (copy and drop in browser)