A new study1 involving people who exercise less than 3 times a week demonstrated that snacking on almonds increased leg and lower back strength, enhanced recovery post-exercise, and reduced fatigue and tension. David C. Nieman, DrPH, FACSM, Professor and Principal Investigator, Human Performance Laboratory, Appalachian State University, led this novel research, supported with funding from the Almond Board of California.
How Do Almonds Promote Muscle Recovery?
Dr. Nieman’s team wanted to see if an almond snack compared to a high-carbohydrate cereal bar snack would improve inflammation and recovery in adults engaging in 90-minute exercise sessions. “What we found tells us definitively that almonds should be added to sports nutrition strategies to help people recover better from exercise,” explained Dr. Nieman.
Here’s everything you need to know about the science behind the study results:
Study participants:
In this trial, participants included 64 healthy adults with an average age of 46 years. Participants were screened and were included if they exercised less than 3 sessions per week.
Study design:
The experiment used a randomized, parallel group design, where treatment participants (n = 33) ate 57 g (2 ounces) of almonds daily, split between morning and afternoon, for 4 weeks prior to a 90-minute exercise bout consisting of 17 different exercises. Control participants (n = 31) consumed a calorie-matched cereal bar, also in split doses.
Participants submitted blood and urine samples and responded to mood and muscle soreness questionnaires. Height, weight, and body composition were measured. Then, people in the study were instructed to perform muscle function tests (exercises), and once complete, they initiated the 4-week supplementation period— eating either almonds or cereal bars. At the conclusion of 4 weeks, participants submitted dietary intake records, blood and urine samples, and another set of questionnaire responses. Muscle function testing was repeated and then participants engaged in 90-minute eccentric exercises. Eccentric exercise is when you are slowly lowering a load, such as lowering to the floor. Examples include sitting lowering into a squat or lowering during a push-up.
Study results:
The study found that almond consumers experienced the following:
- reduced post-exercise fatigue and tension as well as higher levels of leg and lower back strength;
- lower levels of serum creatine kinase, which is a marker of muscle damage, immediately and one day after exercise;
- higher levels of the oxylipin (molecules that affect muscle function, recovery, and fat burn) 12,13-DiHOME and lower levels for oxylipin 9,10-DiHOME;
- increased urine levels of phenolics derived in the large intestine (indicates consumption of polyphenols from almonds, and polyphenols are naturally occurring plant compounds that protect plants and may benefit human health);
- some improvement to mood state following the intervention.
Study limitation:
A limitation of the research is that it only included non-smoking participants without obesity who exercised occasionally (less than three times per week); therefore, we cannot generalize the findings to other demographic and health status groups.
Study conclusions:
- Positive changes in several parameters were found in the almond group,
including decreases in 9,10 DiHOME and increases in 12,13-DiHOME, which has been
shown to support beneficial metabolic outcomes. Overall, almond consumption was shown to be beneficial to the inflammatory response following exercise in untrained men and women without obesity.
- Almond consumption was associated with lower levels of serum creatine kinase
immediately after and 1st day post-exercise. Physical exercise can increase blood
creatine kinase levels, and elevated levels can indicate muscle damage.
- Subjects in the almond group experienced reduced feelings of fatigue and
tension, better leg and lower back strength during recovery, and decreased muscle damage during the first day of recovery.