Higher Institute of Sport and Physical Education of Ksar said, Tunis, Tunisia.
University of Split, Faculty of Kinesiology, Split, Croatia; Tunisian Research Laboratory Sport Performance Optimization, National Center of Medicine and Science in Sports, Tunis, Tunisia.
Nutrition. 2018 Jul-Aug;51-52:29-37. doi: 10.1016/j.nut.2017.12.014. Epub 2018 Feb 3.
This study examined the effect of 12 wk of time-restricted feeding (TRF) on complete blood cell counts, natural killer cells, and muscle performance in 20- and 50-year-old men.
Forty active and healthy participants were randomly divided into young experimental, young control, aged experimental, and aged control group. Experimental groups participated in TRF. Before (P1) and after (P2) TRF, participants performed a maximal exercise test to quantify muscle power. Resting venous blood samples were collected for blood count calculation.
No changes were identified in muscle power in all groups after TRF (P > 0.05). At P1, red cells, hemoglobin, and hematocrit were significantly higher in young participants compared with elderly participants (P < 0.05). At P2, this age effect was not found in red cells between the young experimental group and the aged experimental group (P > 0.05). At P1, white blood cells and neutrophils were significantly higher in young participants compared with elderly participants (P < 0.05). At P2, only neutrophils decreased significantly (P < 0.05) in experimental groups without significant (P > 0.05) difference among them. Lymphocytes decreased significantly in the aged experimental group at P2 (P < 0.05), whereas NKCD16 and NKCD56 decreased significantly in experimental groups at P2 (P < 0.05). TRF had no effect on CD3, CD4, and CD8 levels (P > 0.05).
TRF decreases hematocrit, total white blood cells, lymphocytes, and neutrophils in young and older men. TRF may be effective in preventing inflammation by decreasing natural killer cells. As such, TRF could be a lifestyle strategy to reduce systemic low-grade inflammation and age-related chronic diseases linked to immunosenescence, without compromising physical performance.
本研究探讨了限时进食（TRF）对 20 岁和 50 岁男性全血细胞计数、自然杀伤细胞和肌肉性能的影响。
40 名活跃且健康的参与者被随机分为年轻实验组、年轻对照组、老年实验组和老年对照组。实验组参与 TRF。在 TRF 前后（P1 和 P2），参与者进行最大运动测试以量化肌肉力量。采集静息静脉血样进行血细胞计数。
TRF 后所有组的肌肉力量均无变化（P>0.05）。在 P1 时，年轻参与者的红细胞、血红蛋白和血细胞比容明显高于老年参与者（P<0.05）。在 P2 时，年轻实验组和老年实验组之间的红细胞没有发现这种年龄效应（P>0.05）。在 P1 时，年轻参与者的白细胞和中性粒细胞明显高于老年参与者（P<0.05）。在 P2 时，只有中性粒细胞显著下降（P<0.05），实验组之间没有显著差异（P>0.05）。在 P2 时，老年实验组的淋巴细胞显著下降（P<0.05），而实验组的 NKCD16 和 NKCD56 在 P2 时显著下降（P<0.05）。TRF 对 CD3、CD4 和 CD8 水平没有影响（P>0.05）。
TRF 降低了年轻和老年男性的红细胞比容、总白细胞、淋巴细胞和中性粒细胞。TRF 通过降低自然杀伤细胞可能对预防炎症有效。因此，TRF 可能是一种生活方式策略，可以减少与免疫衰老相关的全身性低度炎症和与年龄相关的慢性疾病，而不会影响身体表现。
