Pietiläinen Kirsi H, Kaprio Jaakko, Borg Patrik, Plasqui Guy, Yki-Järvinen Hannele, Kujala Urho M, Rose Richard J, Westerterp Klaas R, Rissanen Aila
Obesity Research Unit, Department of Psychiatry, Helsinki University Central Hospital, Helsinki, Finland.
Obesity (Silver Spring). 2008 Feb;16(2):409-14. doi: 10.1038/oby.2007.72.
Physical activity (PA) begins to decline in adolescence with a concomitant increase in weight. We hypothesized that a vicious circle may arise between decreasing PA and weight gain from adolescence to early adulthood.
PA and self-perceived physical fitness assessed in adolescents (16-18 years of age) were used to predict the development of obesity (BMI > or =30 kg/m(2)) and abdominal obesity (waist >/=88 cm in females and > or =102 cm in males) at age 25 in 4,240 twin individuals (90% of twins born in Finland, 1975-1979). Ten 25-year-old monozygotic (MZ) twin pairs who were discordant for obesity (with a 16 kg weight difference) were then carefully evaluated for current PA (using a triaxial accelerometer), total energy expenditure (TEE, assessed by means of the doubly labeled water (DLW) method), and basal metabolic rate (BMR, assessed by indirect calorimetry).
Physical inactivity in adolescence strongly predicted the risk for obesity (odds ratio (OR) 3.9, 95% confidence interval (CI) 1.4-10.9) and abdominal obesity (4.8, 1.9-12.0) at age 25, even after adjusting for baseline and current BMI. Poor physical fitness in adolescence also increased the risk for overall obesity (5.1, 2.0-12.7) and abdominal obesity (3.2, 1.5-6.7) in adulthood. Physical inactivity was both causative and secondary to the development of obesity discordance in the MZ pairs. TEE did not differ between the MZ co-twins. PA was lower whereas BMR was higher in the obese co-twins.
Physical inactivity in adolescence strongly and independently predicts total (and especially) abdominal obesity in young adulthood, favoring the development of a self-perpetuating vicious circle of obesity and physical inactivity. Physical activity should therefore be seriously recommended for obesity prevention in the young.
身体活动（PA）在青少年时期开始下降，同时体重增加。我们假设从青少年到成年早期，PA下降和体重增加之间可能会形成恶性循环。
在4240对双胞胎个体（90%为1975 - 1979年出生于芬兰的双胞胎）中，利用青少年（16 - 18岁）时期评估的PA和自我感知的身体健康状况来预测25岁时肥胖（体重指数（BMI）≥30 kg/m²）和腹型肥胖（女性腰围≥88 cm，男性腰围≥102 cm）的发生情况。随后，对10对25岁时肥胖情况不一致（体重相差16 kg）的同卵双胞胎（MZ）进行了仔细评估，测量他们当前的PA（使用三轴加速度计）、总能量消耗（TEE，通过双标记水（DLW）法评估）和基础代谢率（BMR，通过间接测热法评估）。
即使在调整了基线和当前BMI后，青少年时期缺乏身体活动仍能强烈预测25岁时肥胖（优势比（OR）3.9，95%置信区间（CI）1.4 - 10.9）和腹型肥胖（4.8，1.9 - 12.0）的风险。青少年时期身体健康状况不佳也会增加成年后总体肥胖（5.1，2.0 - 12.7）和腹型肥胖（3.2，1.5 - 6.7）的风险。在MZ双胞胎对中，缺乏身体活动既是肥胖不一致发展的原因，也是其结果。MZ双胞胎的同卵双胞胎之间TEE没有差异。肥胖的同卵双胞胎PA较低而BMR较高。
青少年时期缺乏身体活动能强烈且独立地预测年轻成年期的总体（尤其是腹型）肥胖，这有利于形成肥胖与身体活动不足的自我持续恶性循环。因此，强烈建议年轻人进行身体活动以预防肥胖。
