|YI, MUQING - National Institute Of Sports Medicine|
|FU, JINDE - National Institute Of Sports Medicine|
|ZHOU, LILI - National Institute Of Sports Medicine|
|GAO, HONG - National Institute Of Sports Medicine|
|FAN, CHENGUANG - National Institute Of Sports Medicine|
|SHAO, JING - National Institute Of Sports Medicine|
|XU, BAOHUA - National Institute Of Sports Medicine|
|WANG, QIRONG - National Institute Of Sports Medicine|
|LI, JUNATO - National Institute Of Sports Medicine|
|HUANG, GUANGWEI - Almond Board Of California|
|LAPSLEY, KAREN - Almond Board Of California|
|BLUMBERG, JEFFREY - Jean Mayer Human Nutrition Research Center On Aging At Tufts University|
|CHEN, C-Y OLIVER - Jean Mayer Human Nutrition Research Center On Aging At Tufts University|
Submitted to: Journal of the International Society of Sports Nutrition 2012 (JISSN)
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/6/2014
Publication Date: 5/11/2014
Citation: Yi, M., Fu, J., Zhou, L., Gao, H., Fan, C., Shao, J., Xu, B., Wang, Q., Li, J., Huang, G., Lapsley, K., Blumberg, J., Chen, C. 2014. The effect of almond consumption on elements of endurance exercise performance in trained athletes. Journal of the International Society of Sports Nutrition 2012 (JISSN). 11:18.
Interpretive Summary: Almonds are rich in a diverse array of nutrients and eating almonds and other tree nuts has been associated with reduced risk for cardiovascular disease. Almonds have also been suggested as a food that provides sustained energy for athletes during training. However, the effect of almonds incorporated into the daily diet of athletes during training on exercise performance has never been tested. Our research objective was to examine the effect of almonds on aspects of endurance exercise performance in trained athletes. We conducted a study with 8 trained male cyclists and 2 triathletes. They were randomly assigned to consume 2.7 ounces of whole almonds per day or 3.2 ounces of cookies daily for 4 weeks. These athletes also underwent 3 performance tests including 125-min steady status exercise and 20-min time trial on an indoor stationary bike at the start of the study (baseline) and at the end of each dietary intervention phase. Consuming almonds significantly increased cycling distance during the time trial compared to eating the control cookies. Almonds increased carbohydrate utilization as a fuel source but decreased fat oxidation utilized during the exercise performance test. Almonds also maintained a higher blood glucose level after the time trial than cookies. Almond consumption enhanced blood levels of the antioxidant vitamin E. Compared to cookies, whole almonds improved cycling distance and endurance performance in these trained athletes through improved efficiencies in the use of carbohydrates and oxygen. These results suggest that almonds can be incorporated into diets of people who undertake exercise training to improve their performance.
Technical Abstract: Almonds are a healthy tree nut food with high nutrient density. Their consumption has been shown to ameliorate oxidative stress, inflammation, etc. The objective of the study was to examine the effect of almonds on elements of endurance exercise performance in trained athletes. A 10-week crossover, placebo controlled study was conducted. Eight trained male cyclists and two triathletes were randomly assigned to consume 75 grams per day whole almonds (ALM) or isocaloric cookies (COK) with equal subject number. They consumed the assigned food for 4 wks and then the alternate food for another 4 wks. They underwent 3 performance tests including 125-min steady status exercise (SS) and 20-min time trial (TT) on an indoor stationary trainer at the start of the study (BL) and at the end of each intervention phase. Venous blood was collected in the morning prior to the performance test for biochemical measurements and finger blood during the test for glucose determination. Carbohydrate and fat oxidation, energy expenditure, and oxygen use were calculated using respiratory gas analysis. ALM increased cycling distance during TT by 1.7 km as compared BL (21.9 vs. 20.2 km, P = 0.053) and COK increased 0.6 km (20.8 vs. 20.2 km, P > 0.05). ALM, but not COK, led to higher CHO and lower fat oxidation and less oxygen consumption during TT than BL (P < 0.05), whereas there was no significant difference in heart rate among BL, ALM and COK. ALM maintained higher blood glucose level after TT than COK (P < 0.05). ALM had higher vitamin E and haemoglobin and lower serum free fatty acid (P < 0.05), slightly elevated serum arginine and nitric oxide and plasma insulin (P > 0.05) than BL, and a higher total antioxidant capacity than COK (P < 0.05).Whole almonds improved cycling distance and the elements related to endurance performance more than isocaloric cookies in trained athletes as some nutrients in almonds may contribute to CHO reservation and utilization and effective oxygen utilization. The results suggest that almonds can be incorporated into diets of those who undertake exercise training for performance improvement.