Figueroa-Colon R, Hunter G R, Mayo M S, Aldridge R A, Goran M I, Weinsier R L
Mead Johnson Nutritionals, Evansville, IN 47721, USA.
Med Sci Sports Exerc. 2000 Apr;32(4):865-9. doi: 10.1097/00005768-200004000-00021.
The main objective of this study was to determine the reliability of measuring treadmill exercise economy (VO2submax) and the maximal oxygen uptake (VO2max) in prepubertal girls tested twice, 6 wk apart. We also wanted to examine the percentage of young girls who were able to reach the criteria for achieving VO2max and to describe methods that would allow a high proportion of young children to achieve criteria for reaching a true VO2max.
We studied 61 normal-weight, prepubertal girls with a mean (+/- SD) age 7.3+/-1.3 yr (range 4.8 to 10.3 yr). VO2submax was determined while walking for 4 min at 2.5 mph with 0% grade. VO2max was measured during a progressive, all-out, continuous treadmill test using standardized procedures and criteria. Heart rate (HR) was measured using a Polar monitor. Respiratory rate (RR), respiratory exchange ratio (RER), ventilation (V), and VO2 were measured using a Sensormedics metabolic monitor.
There were no significant differences between visits I and 2 in mean HR, RR, RER, V, VO2submax (421 vs 422 mL x min(-1), respectively), and VO2max (1036 vs 1049 mL x min(-1), respectively). Intra-individual coefficients of variation (CV) between visits 1 and 2 for submaximal tests were: HR = 5.1%, RR = 12.4%, RER = 7.2%, V = 12.5%, and VO2 = 12.4%. Intra-individual CVs for the maximum tests were: HRmax = 2.1%, RRmax = 10.8%, RERmax = 5.3%, Vmax = 11.7%, and VO2max = 7.5%. A high proportion of the girls reached criteria for VO2max [RER> 1.00, HR>85% of age predicted maximum, and plateauing of VO2max] in both visits: 99% reached one of three criteria, 92% reached two of three criteria, and 70% reached all three criteria. Twenty girls [mean age 7.2+/-1.2 yr] reached at least two criteria in both visits, whereas 32 girls [mean (+/- SD) age 8.6+/-1.0 yr] reached three criteria in both visits.
Exercise measurements using treadmill testing were reliable in healthy, normal-weight, prepubertal girls. Older girls when compared to the younger girls were able to reach criteria for VO2max more often. Thus, we recommend that one testing should give researchers an accurate measure of walking economy and aerobic capacity, and that two criteria are enough for determining VO2max.
本研究的主要目的是确定对青春期前女孩进行两次测试（间隔6周）时，测量跑步机运动经济性（最大摄氧量下的耗氧量，VO₂submax）和最大摄氧量（VO₂max）的可靠性。我们还想研究能够达到VO₂max标准的年轻女孩的比例，并描述能使很大比例的幼儿达到真正VO₂max标准的方法。
我们研究了61名体重正常的青春期前女孩，平均年龄（±标准差）为7.3±1.3岁（范围4.8至10.3岁）。以2.5英里/小时的速度在0%坡度下步行4分钟时测定VO₂submax。使用标准化程序和标准，在递增、全力、持续的跑步机测试中测量VO₂max。使用Polar监测仪测量心率（HR）。使用Sensormedics代谢监测仪测量呼吸频率（RR）、呼吸交换率（RER）、通气量（V）和VO₂。
第一次和第二次测试之间，平均心率、RR、RER、V、VO₂submax（分别为421与422 mL·min⁻¹）和VO₂max（分别为1036与1049 mL·min⁻¹）均无显著差异。两次测试之间，次最大测试的个体内变异系数（CV）为：HR = 5.1%，RR = 12.4%，RER = 7.2%，V = 12.5%，VO₂ = 12.4%。最大测试的个体内CV为：HRmax = 2.1%，RRmax = 10.8%，RERmax = 5.3%，Vmax = 11.7%，VO₂max = 7.5%。在两次测试中，很大比例的女孩达到了VO₂max标准[RER>1.00，HR>预测的年龄最大心率的85%，且VO₂max达到平台期]：99%达到三项标准中的一项，92%达到三项标准中的两项，7%达到全部三项标准。20名女孩[平均年龄7.2±1.2岁]在两次测试中至少达到两项标准，而32名女孩[平均（±标准差）年龄8.6±1.0岁]在两次测试中达到三项标准。
在健康、体重正常的青春期前女孩中，使用跑步机测试进行运动测量是可靠的。与年幼女孩相比，年长女孩更常能达到VO₂max标准。因此，我们建议一次测试就能为研究人员提供步行经济性和有氧能力的准确测量，并且两项标准足以确定VO₂max。
