Eating This Nut Every Day Can Boost Exercise Recovery, Study Suggests

Sports drinks aren’t the only solution for replenishing muscles post-workout. According to a small randomized-control study published in Frontiers in Nutrition, eating a simple handful of almonds each day may actually boost muscles during exercise recovery, reduce fatigue, and improve inflammation in the body.

“In the last decade or two, we’re realizing that sports nutrition is more than just water and carbohydrate,” said one of the study’s researchers, Dr. David C. Nieman, DrPH, FACSM, professor and principal investigator from Appalachian State University, in an interview with Clean Plates. “The reason we focused on almonds is because they have a nutrient mix that theoretically should be conducive to supporting exercise and metabolic recovery from exercise.” (Note: The study was supported by the Almond Board of California.)

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How the researchers conducted their study

Because previous exercise recovery has focused on carbohydrate intake post-workout, Dr. Nieman and the team of researchers decided to split 64 non-obese adults not engaging in regular exercise into two groups. One group would consume 57 grams (around 2 ounces) of almonds a day, while the other group consumed a calorie-matched cereal bar.

Both groups were then required to do a 90-minute workout on weekends (to match the “weekend warrior” mindset, where people save exercise for the weekends), continuing to supplement with their allotted food for four weeks. By the end, participants were asked to fill out a questionnaire with responses about muscle soreness and mood, while also submitting urine and blood samples.

With these findings, the researchers concluded that the almond-eating group experienced reduced post-exercise fatigue and tension, higher levels of leg and lower back strength, reduced levels of serum creatine kinase (a marker of muscle damage), and improvement in mood. Researchers were also pleasantly surprised to find higher levels of oxylipin in the blood, a type of molecule that affects muscle function, recovery, and fat burning.

Polyphenols in almonds play a major role in recovery

One of the most significant findings that Dr. Nieman determined to be the crucial element to his exercise recovery research has to do with the polyphenols (a type of antioxidant) found in the skin of almonds. Increased urine levels in the almond-eating group was the tip-off initially, given that this bodily response is an indicator of high consumption of polyphenols.

This isn’t the first time polyphenols have been researched for exercise recovery. Dr. Nieman explains how researchers have tried replacing “sugar water” (aka, traditional sports drinks) with athletes consuming fruits with water in the past — such as bananas, watermelon, pears, apples, and blueberries. Blueberries showed promising results for exercise recovery for athletes, so finding that the polyphenols from almonds also worked to that same positive effect was the “aha” moment researchers like Dr. Nieman were looking for.

“What a lot of people don’t know is, like the blue and blueberries or the brown skins and almonds, these polyphenols go to the gut,” Dr. Nieman says. “The polyphenols are complex molecules that have to be broken down and the bacteria in the gut become a partner in this process. They break up the molecules into smaller pieces that then can escape to the colon and circulate through the body. These are anti-oxidative, anti-inflammatory, and bioactive — we need these things for human health. And now we have found [they benefit] metabolic recovery from exercise as well.”

“The reason [we focused] on the polyphenols is because we found that one of the metabolites coming out of the gut after they were eating the almond polyphenols was a metabolite that then was negatively correlated with this bad 9,10-DiHOME,” he continues.

The 9,10-DiHOME is a plasma oxylipin that can be toxic to the body’s tissues, yet for the almond-eating group, the researchers found that the polyphenols helped to knock down this oxylipin in the gut, improving one’s exercise recovery and mood. On the other hand, the 12,13-DiHOME oxylipin levels were increased, which Dr. Nieman also explains can benefit recovery.

“It actually helps your muscle mitochondria burn fats better, so it’s kind of a fat-burning metabolite,” he explains. “Those eating almonds had higher levels of that, which, after this weekend warrior exercise, improved their metabolic recovery.”

One handful of almonds won’t fix the problem

Dr. Nieman notes that eating almonds once won’t do it; the polyphenols take time to work in the gut to make a significant difference in post-exercise recovery. This means that athletes should be eating this snack daily over time.

“It takes at least two weeks of eating extra polyphenols in the diet for the bacteria in the gut to adjust to that new substrate coming into the colon,” he explains. “[This is] what we call a ‘loading period’ when it comes to using polyphenols. When we got into fruit like blueberries, we told athletes our research supported a cup a day for two weeks. Now in this study, just to be safe because we didn’t know much about almonds, we did four weeks before they came in. But my speculation is that two weeks might work.”

Dr. Nieman also points out that the skins of the almonds are where the polyphenols come from, so simply adding almond milk to your protein shake may not be the solution for this workout recovery snack. Instead, a handful of almonds a day will do — or sprinkle them on a yogurt bowl with blueberries for the ultimate post-exercise boost.

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