Spinach is nutritionally dense, as are leafy greens generally. We know this. But while spinach gets a good rap for its iron content (largely overstated), there is a much more critical component to be mindful of. Because of the abundance of organic nitrates contained within the leaves, our muscles perform more efficiently when we’re regularly consuming it. This, we don’t discuss enough.
Our aim was to assess whether a high-nitrate diet increases nitric oxide bioavailability and to evaluate the effects of this nutritional intervention on exercise performance. Seven healthy male subjects participated in a randomized cross-over study. They were tested before and after 6 days of a high (HND) or control (CD) nitrate diet (~8.2 mmol∙day−1 or ~2.9 mmol∙day−1, respectively). Plasma nitrate and nitrite concentrations were significantly higher in HND (127 ± 64 µM and 350 ± 120 nM, respectively) compared to CD (23 ± 10 µM and 240 ± 100 nM, respectively). In HND (vs. CD) were observed: (a) a significant reduction of oxygen consumption during moderate-intensity constant work-rate cycling exercise (1.178 ± 0.141 vs. 1.269 ± 0.136 L·min−1); (b) a significantly higher total muscle work during fatiguing, intermittent sub-maximal isometric knee extension (357.3 ± 176.1 vs. 253.6 ± 149.0 Nm·s·kg−1); (c) an improved performance in Repeated Sprint Ability test. These findings suggest that a high-nitrate diet could be a feasible and effective strategy to improve exercise performance.
I’m writing this post for my boys, for my fellow athletes and for carnivores like me who, at one point or another in their culinary explorations, included zero greens on their plates in favor of simple flesh and other “muscle building” foods.
This evening, my badass son Dane (AKA 22) declared that, at 15 years old and 125 pounds, “I squatted 225 x 5, killed box jumps and ran stairs.” He then told me, “my legs won’t work tomorrow.” As we conversed, we waltzed into Vintage (our local grocery store) to grab him some dinner. We left with his meal, tri-tip in a cardboard to-go box, which he began tearing into in the car (fine, I did too). I then dropped him off and split to run my sprints (for you sprint enthusiasts, I did thirty seconds x 4 at a 30 degree incline). I polished off my workout with 4 40s and 4 60s, thinking about food between sets.
Perhaps the sprints gave me clarity, but I knew I needed to talk to Dane about nutritional value at the margins. Like me, and his brother, and most athletes we know (sans Tony Gonzalez), he eats his animals, he gets his starches, but he’s missing his spinach. As hard as he’s training, he can’t afford to punt on that value. After my own training session, I grabbed two large handfuls of greens, stuffed them in my mouth and chewed while reading this from Breaking Muscle:
When changing your diet to promote lean muscle growth, simply increasing your protein intake is not enough. Some fitness enthusiasts often neglect the importance of vegetables in their diets. Although higher protein and complex carbohydrate intake is important, vegetables also provide essential minerals and nutrients that promote fat loss, muscle recovery, and muscle growth. Spinach and broccoli are great sources of folic acid, which repairs DNA and helps to produce new red blood cells.4 Brussels sprouts and broccoli are great sources of Vitamin C, which supports the immune system and protects the body from oxidative stress.5Broccoli is a good source of zinc, which plays a role in immune function, protein synthesis, wound healing.6 Spinach is a great source of magnesium, which helps to maintain normal muscle and nerve function and supports the immune system. Vegetables in the Brassica family, such as broccoli, cauliflower, and cabbage, are also great sources of fiber.
More specifically, and because it’s such an easy add, I was curious about spinach and its impact on lean tissue development. If you want to convince an elite male athlete (or your developing young men) to eat greens, don’t tell him that he’ll get fewer colds. Tell him he’ll be more powerful and maybe develop a ripped up torso. Those nitrates we talked about make a significant difference.
And it turns out that spinach is loaded with these nitrates, which are converted into NO and used throughout the body. Professors Eddie Weitzberg and Jon Lundberg, coauthors of the Swedish study, observed that consuming the nitrate equivalent of 200-300g of spinach for just three days along with intense exercise improves mitochondrial efficiency. This in turn reduces oxygen consumption and increases the production of energy-rich substances in muscle tissue, resulting in both improved muscle gains and better overall health.
When it comes to eating for strength, power and muscle, consider your meat and potatoes your blocking and tackling. Gonna be hard to win without those things. But maybe your spinach is your star slot receiver….your Doug Baldwin or your Julian Edelman. The Pats and the Seahawks are great leadership groups hunting for value at the margins. See what I did there with the football analogies, 22? Now eat your damn spinach.