Department of Radiology, University of Washington, Seattle, WA, USA.
Exercise Research Center, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
Physiol Rep. 2021 Jun;9(11):e14887. doi: 10.14814/phy2.14887.
Endurance training (ET) is recommended for the elderly to improve metabolic health and aerobic capacity. However, ET-induced adaptations may be suboptimal due to oxidative stress and exaggerated inflammatory response to ET. The natural antioxidant and anti-inflammatory dietary supplement astaxanthin (AX) has been found to increase endurance performance among young athletes, but limited investigations have focused on the elderly. We tested a formulation of AX in combination with ET in healthy older adults (65-82 years) to determine if AX improves metabolic adaptations with ET, and if AX effects are sex-dependent. Forty-two subjects were randomized to either placebo (PL) or AX during 3 months of ET. Specific muscle endurance was measured in ankle dorsiflexors. Whole body exercise endurance and fat oxidation (FATox) was assessed with a graded exercise test (GXT) in conjunction with indirect calorimetry. Results: ET led to improved specific muscle endurance only in the AX group (Pre 353 ± 26 vs. Post 472 ± 41 contractions), and submaximal GXT duration improved in both groups (PL 40.8 ± 9.1% and AX 41.1 ± 6.3%). The increase in FATox at lower intensity after ET was greater in AX (PL 0.23 ± 0.15 g vs. AX 0.76 ± 0.18 g) and was associated with reduced carbohydrate oxidation and increased exercise efficiency in males but not in females.
耐力训练（ET）被推荐用于老年人，以改善代谢健康和有氧能力。然而，由于氧化应激和对 ET 的过度炎症反应，ET 诱导的适应可能不理想。天然抗氧化剂和抗炎膳食补充剂虾青素（AX）已被发现可提高年轻运动员的耐力表现，但对老年人的研究有限。我们测试了一种 AX 配方与 ET 的联合应用，以确定 AX 是否可以改善 ET 引起的代谢适应，以及 AX 的效果是否存在性别依赖性。42 名受试者被随机分为安慰剂（PL）或 AX 组，进行 3 个月的 ET。特定的肌肉耐力在踝关节背屈肌中进行测量。全身运动耐力和脂肪氧化（FATox）通过与间接测热法相结合的递增运动测试（GXT）进行评估。结果：ET 仅在 AX 组中导致特定肌肉耐力的提高（预 353±26 次与后 472±41 次收缩），并且两组的亚最大 GXT 持续时间都有所提高（PL 40.8±9.1%和 AX 41.1±6.3%）。ET 后低强度时 FATox 的增加在 AX 组中更大（PL 0.23±0.15 g 与 AX 0.76±0.18 g），并且与男性的碳水化合物氧化减少和运动效率增加有关，但与女性无关。
