Ginsburg G S, Agil A, O'Toole M, Rimm E, Douglas P S, Rifai N
Cardiovascular Division, Beth Israel Hospital, Boston, MA 02215, USA.
JAMA. 1996 Jul 17;276(3):221-5.
To determine the effects of a single bout of ultraendurance exercise, as a model for physiologic stress, on lipid and lipoprotein levels, and oxidative susceptibility of lipids in highly trained athletes.
Observational trial.
Thirty-nine volunteer subjects (26 mean, 13 women; mean age, 38 +/- 10 years) who competed in and completed the 1994 Hawaii Ironman World Championship Triathlon consisting of a consecutive 3.9-km (2.4-mi) swim, 180.2-km (112-mi) bike ride, and a 42.2-km (26.2-mi) run. Subjects answered questionnaires and had blood samples obtained 2 days prior to and within 15 minutes of completion of the triathlon.
Prerace vs postrace changes in lipid and lipoprotein levels, and susceptibility of lipids to peroxidation.
The mean duration of exercise was 753 +/- 128 minutes. With exercise, plasma volume-corrected levels of triglycerides decreased 39% from 1.58 +/- 0.83 to 0.97 +/- 0.68 mmol/L (139.6 +/- 73.6 to 85.8 +/- 60.5 mg/dL) (P < .001). Levels of total cholesterol decreased 9% from 4.94 +/- 0.88 to 4.50 +/- 0.79 mmol/L (190.8 +/- 33.8 to 173.8 +/- 30.6 mg/dL) (P < .001), low-density lipoprotein cholesterol decreased 11% from 2.59 +/- 0.77 to 2.30 +/- 0.86 mmol/L (100.1 +/- 29.9 to 88.7 +/- 33.3 mg/dL) (P = .02), and apolipoprotein B decreased 10% from 0.91 +/- 0.20 to 0.82 +/- 0.18 g/L (90.7 +/- 20.0 to 82.0 +/- 17.9 mg/dL) (P < .001). High-density lipoprotein cholesterol and apolipoprotein A-I increased with exercise but not significantly. The susceptibility of lipids to peroxidation decreased significantly (4.51 +/- 1.91 micromol/L, preexercise, vs 2.42 +/- 2.27 micromol/L, postexercise, P < .001), an effect that was not related to antioxidant use or levels of vitamins A, C, or E. Serum iron, a potential pro-oxidant, also decreased by 45% with exercise from 15.75 +/- 5.55 to 8.59 +/- 4.30 micromol/L (88 +/- 31 to 48 +/- 24 micrograms/dL) (P < .001), an effect that was weakly correlated with changes in lipid peroxidation (P = .05).
These data suggest that a single bout of prolonged exercise can reduce lipid and lipoprotein risk factors for developing cardiovascular disease. Moreover, susceptibility of lipids to peroxidation is reduced by exercise, thereby adding to the benefits of physical activity. This effect appears to be independent of antioxidant supplement use and may be mediated by induction of endogenous antioxidants. These observations may explain in part the reduced risk of developing vascular and other diseases in individuals who are physically active.
以单次超耐力运动作为生理应激模型，确定其对高水平训练运动员血脂和脂蛋白水平以及脂质氧化易感性的影响。
观察性试验。
39名志愿者（26名男性，13名女性；平均年龄38±10岁），他们参加并完成了1994年夏威夷铁人三项世界锦标赛，该比赛包括连续进行的3.9公里（2.4英里）游泳、180.2公里（112英里）自行车骑行和42.2公里（26.2英里）跑步。研究对象填写问卷，并在铁人三项赛前2天和赛后15分钟内采集血样。
赛前与赛后血脂和脂蛋白水平的变化，以及脂质过氧化的易感性。
运动平均时长为753±128分钟。运动后，经血浆容量校正的甘油三酯水平从1.58±0.83毫摩尔/升降至0.97±0.68毫摩尔/升（139.6±73.6至85.8±60.5毫克/分升），降幅为39%（P<.001）。总胆固醇水平从4.94±0.88毫摩尔/升降至4.50±0.79毫摩尔/升（190.8±33.8至173.8±30.6毫克/分升），降幅为9%（P<.001）；低密度脂蛋白胆固醇从2.59±0.77毫摩尔/升降至2.30±0.86毫摩尔/升（100.1±29.9至88.7±33.3毫克/分升），降幅为11%（P=.02）；载脂蛋白B从0.91±0.20克/升降至0.82±0.18克/升（90.7±20.0至82.0±17.9毫克/分升），降幅为10%（P<.001）。高密度脂蛋白胆固醇和载脂蛋白A-I随运动增加，但无显著差异。脂质过氧化的易感性显著降低（运动前为4.51±1.91微摩尔/升，运动后为2.42±2.27微摩尔/升，P<.001），这一效应与抗氧化剂使用或维生素A、C、E水平无关。血清铁作为一种潜在的促氧化剂，运动后也从15.75±5.55微摩尔/升降至8.59±4.30微摩尔/升（88±31至48±24微克/分升），降幅为45%（P<.001），该效应与脂质过氧化变化呈弱相关（P=.05）。
这些数据表明，单次长时间运动可降低心血管疾病发生的血脂和脂蛋白风险因素。此外，运动可降低脂质过氧化的易感性，从而增加体育活动的益处。这一效应似乎独立于抗氧化剂补充剂的使用，可能是由内源性抗氧化剂的诱导介导的。这些观察结果可能部分解释了体育活动人群血管疾病和其他疾病风险降低的原因。
