University Lyon 1, CarMeN, U1060 INSERM, INSA Lyon, INRA, Lyon, France.
Acta Physiol (Oxf). 2013 Mar;207(3):516-23. doi: 10.1111/apha.12045. Epub 2012 Dec 27.
Intramyocellular lipid (IMCL) variations in older men are poorly explored. In young adults, IMCL can be influenced by both diet and exercise interventions; this flexibility is related to aerobic fitness. We evaluated in active older adults the influence of maximal aerobic capacity on short-term diet and exercise-induced variations in IMCL stores.
Intramyocellular lipids were measured by (1) H magnetic resonance spectroscopy ((1) H-MRS) after a 3-day fat depletion-replenishment diet (IMCL(FDR) ) and immediately after a 2-h exercise at 50% VO(2) max (IMCL(FDR) () (EX) ). To further explore diet influence, the protocol was repeated after a high-fat diet (HF), with both pre- and post-exercise measurements (IMCL(HF) and IMCL(HF) () (EX) ).
In active older men (69.8 ± 5.2 years), IMCL(FDR) was lowered by exercise (IMCL(FDR) = 3.45 ± 1.52 vs. IMCL(FDR) (_) (EX) = 2.74 ± 1.15 mmol kg(-1) wet weight, P < 0.05), and exercise-induced variations were correlated to the initial store (P < 0.05, r = -0.72). IMCL(FDR) was linked with aerobic fitness (P < 0.05, r = 0.76), when adjusted by fat mass. IMCL(HF) was lower than IMCL(FDR) (P < 0.05), decreased after exercise (P < 0.05) and varied also as a function of initial store (P < 0.05, r = -0.89), but without link with aerobic fitness. Finally, diet-induced IMCL store variations were positively linked to aerobic fitness (P < 0.05, r = 0.89).
Variations of the IMCL stores in physically active older adults appear related to aerobic fitness, with similarly fast adaptation to short-term interventions combining diet and exercise as young active adults.
老年人的肌内脂质（IMCL）变化尚未得到充分研究。在年轻人中，IMCL 既受饮食也受运动干预的影响；这种灵活性与有氧健身能力有关。我们评估了活跃的老年人最大有氧能力对 IMCL 储存的短期饮食和运动诱导变化的影响。
在进行为期 3 天的脂肪耗竭补充饮食（IMCL(FDR)）后，通过（1）H 磁共振波谱（（1）H-MRS）测量肌内脂质，然后立即在 50% VO(2)max 时进行 2 小时运动（IMCL(FDR)（）（EX））。为了进一步探索饮食的影响，在高脂肪饮食（HF）后重复该方案，并在运动前后进行测量（IMCL(HF)和 IMCL(HF)（）（EX））。
在活跃的老年男性（69.8 ± 5.2 岁）中，运动降低了 IMCL(FDR)（IMCL(FDR) = 3.45 ± 1.52 vs. IMCL(FDR)（_）（EX）= 2.74 ± 1.15 mmol kg(-1)湿重，P < 0.05），运动诱导的变化与初始储存量相关（P < 0.05，r = -0.72）。当调整脂肪质量时，IMCL(FDR)与有氧健身能力相关（P < 0.05，r = 0.76）。IMCL(HF)低于 IMCL(FDR)（P < 0.05），运动后降低（P < 0.05），并且还与初始储存量呈函数关系（P < 0.05，r = -0.89），但与有氧健身能力无关。最后，饮食引起的 IMCL 储存变化与有氧健身能力呈正相关（P < 0.05，r = 0.89）。
在身体活跃的老年人中，IMCL 储存的变化似乎与有氧健身能力有关，与年轻活跃成年人一样，能够快速适应结合饮食和运动的短期干预。
