Eating almonds daily boosts exercise recovery molecule by 69% among ‘weekend warriors’
Abstract: Adding 57 g of almonds to the diet every day for a month increases the levels of the beneficial fat, 12,13-DiHOME in blood samples immediately after intense exercise.
For those who exercise regularly, an ideal New Year’s resolution might be to eat almonds every day.
Randomized controlled trial in Dietary limits showed that male and female participants who ate 57 g of almonds per day for one month had more of the beneficial fat 12,13-dihydroxy-9Z-octadecenoic acid (12,13-DiHOME) in their blood immediately after an intense exercise session than control participants.
This molecule, the so-called oxylipin (oxidized fat) is synthesized from linoleic acid in brown adipose tissue and has a beneficial effect on metabolic health and energy regulation.
Corresponding author Dr. David C Nieman, professor and director of the Human Performance Laboratory at Appalachian State University’s North Carolina Research Campus, said: “Here we show that volunteers who consumed 57 g of almonds per day for one month prior to a ‘weekend warrior’ exercise session they had more beneficial 12,13-DiHOME in their blood immediately after exercise than control volunteers. They also reported feeling less fatigue and tension, better leg and back strength, and reduced muscle damage after exercise than control volunteers.”
A four-week dietary supplement with almonds
38 men and 26 women between the ages of 30 and 65, who did not regularly exercise with weights, participated in the clinical trial. About half were randomized to the almond diet group, and the other half to the control group, which ate a cereal bar of the appropriate calorie content every day. The researchers took blood and urine samples before and after a four-week dietary supplementation period.
Performance measures included the 30-second Wingate anaerobic test, the 50-meter run test, and the vertical jump, bench press, and leg strength exercises. Additional blood and urine samples were taken immediately after this 90-minute ‘eccentric exercise’ session and daily for four days thereafter.
After each blood draw, participants completed the ‘Profile of Mood States’ (POMS) questionnaire to quantify their mental state and rate their delayed muscle soreness – that is, the pain and stiffness they feel after unusual or strenuous exercise – on a 10- scale.
As expected, the 90-minute exercise led to an increase in the volunteers’ self-reported sense of muscle damage and muscle soreness, as well as an increased POMS score, indicating decreased strength, and increased fatigue, anxiety and depression.
Exercise also resulted in transiently elevated blood levels of pro-inflammatory cytokines such as IL-6, IL-8, IL-10, and MCP-1, consistent with less muscle damage. However, these changes in cytokines were equal in the almond and cereal groups.
Differences in the two concentrations of DiHOME
Importantly, immediately after exercise, the concentration of beneficial 12,13-DiHOME was 69% higher in the blood plasma of participants in the almond group than in participants in the control group. 12,13-DiHOME is known to increase fatty acid transport and uptake into skeletal muscle, with the overall effect of stimulating metabolic recovery after exercise.
The opposite pattern was found for another oxylipin, the mildly toxic 9,10-dihydroxy-12-octadecenoic acid (9,10-diHOME), which was 40% higher immediately after exercise in the blood of the control group than in the almond group. Unlike 12,13-DiHOME, 9,10-diHOME has been shown to have negative effects on the body’s overall health and recovery from exercise.
The polyphenols in almond skins may be key
Nieman and colleagues concluded that daily consumption of almonds leads to changes in metabolism, reducing inflammation and oxidative stress caused by exercise and allowing the body to recover faster.
“We conclude that almonds provide a unique and complex blend of nutrients and polyphenols that may support metabolic recovery after stressful levels of exercise. Almonds have high amounts of protein, healthy fats, vitamin E, minerals and fiber. And the brown skin of almonds contains polyphenols that end up in the colon and help control inflammation and oxidative stress,” said Nieman.
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be interpreted as a potential conflict of interest.
Financing: Funded by Almond Board of California, Modesto, CA. The funder had no role in study design, data collection, analysis and interpretation, manuscript preparation, or the decision to submit the article for publication.
About this nutrition and exercise research news
Original research: Open access.
“Almond intake alters the acute plasma dihydroxy-octadecenoic acid (DiHOME) response to eccentric exercise” by David Nieman et al. Dietary limits
Almond intake alters the acute plasma dihydroxy-octadecenoic acid (DiHOME) response to eccentric exercise
This research determined whether taking nutrient-dense almonds for 4 weeks reduced post-exercise inflammation and muscle soreness and damage. An acute 90-minute bout of eccentric exercise (90-EE) was used to induce muscle damage in 64 non-obese, non-regular resistance-trained adults (aged 30-65 years, BMI <30 kg/m2).
Using a parallel-group design, participants were randomized to almond (AL) (57 g/day) or cereal bars (CB) (calorie-matched) for a 4-week period prior to 90-EE (17 exercises).
Blood and 24-h urine samples were collected before and after supplementation, with additional blood samples collected immediately after 90-EE and then daily for 4 additional days of recovery. Changes in plasma oxylipins, urinary gut-derived phenols, plasma cytokines, biomarkers of muscle damage, mood, and exercise performance were assessed.
The 90-EE protocol caused significant muscle damage, delayed onset muscle soreness (DOMS), inflammation, decreased strength and power, and mood disturbance. Interaction effects (2 groups x 7 time points) supported that AL versus CB was associated with reduced post-exercise fatigue and tension (p=0.051, 0.033, respectively) and higher levels of leg and back strength (p=0.029). No group differences were found for increases in DOMS and six cytokines after 90-EE. AL was associated with lower serum creatine kinase levels immediately and 1 day after exercise (p=0.034 and 0.013, respectively).
A 90-EE challenge increased 13 oxylipin immediately after exercise in plasma. Interaction effects revealed significantly higher levels for AL versus CB for 12,13-DiHOME (p<0.001) and lower levels for 9,10-DiHOME (p<0.001). Urinary levels increased in AL relative to CB for seven gut-derived phenols including 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone which was inversely proportional to changes in plasma 9,10-DiHOME (r=- 0.029, p =0.021).
These data support some positive effects of almond intake in improving mood, maintaining strength, reducing muscle damage, increasing the generation of gut-derived phenolic metabolites, and altering plasma oxylipin DiHOME responses to unusual eccentric exercise in untrained adults.
Elevated post-exercise plasma levels of 12,13-DiHOME with almond intake support positive metabolic outcomes for adults engaging in unusual eccentric bouts of exercise.