Schagatay Erika, Richardson Matt X, Lodin-Sundström Angelica
Department of Engineering and Sustainable Development, and Swedish Winter Sports Research Centre, Mid Sweden University Östersund, Sweden.
Front Physiol. 2012 Jun 18;3:173. doi: 10.3389/fphys.2012.00173. eCollection 2012.
Humans share with seals the ability to contract the spleen and increase circulating hematocrit, which may improve apneic performance by enhancing gas storage. Seals have large spleens and while human spleen size is small in comparison, it shows great individual variation. Unlike many marine mammals, human divers rely to a great extent on lung oxygen stores, but the impact of lung volume on competitive apnea performance has never been determined. We studied if spleen- and lung size correlated with performance in elite apnea divers. Volunteers were 14 male apnea world championship participants, with a mean (SE) of 5.8 (1.2) years of previous apnea training. Spleen volume was calculated from spleen length, width, and thickness measured via ultrasound during rest, and vital capacity via spirometry. Accumulated competition scores from dives of maximal depth, time, and distance were compared to anthropometric measurements and training data. Mean (SE) diving performance was 75 (4) m for constant weight depth, 5 min 53 (39) s for static apnea and 139 (13) m for dynamic apnea distance. Subjects' mean height was 184 (2) cm, weight 82 (3) kg, vital capacity (VC) 7.3 (0.3) L and spleen volume 336 (32) mL. Spleen volume did not correlate with subject height or weight, but was positively correlated with competition score (r = 0.57; P < 0.05). Total competition score was also positively correlated with VC (r = 0.54; P < 0.05). The three highest scoring divers had the greatest spleen volumes, averaging 538 (53) mL, while the three lowest-scoring divers had a volume of 270 (71) mL (P < 0.01). VC was also greater in the high-scorers, at 7.9 (0.36) L as compared to 6.7 (0.19) L in the low scorers (P < 0.01). Spleen volume was reduced to half after 2 min of apnea in the highest scoring divers, and the estimated resting apnea time gain from the difference between high and low scorers was 15 s for spleen volume and 60 s for VC. We conclude that both spleen- and lung volume predict apnea performance in elite divers.
人类与海豹一样，具有收缩脾脏并提高循环血细胞比容的能力，这可能通过增加气体储存来改善屏气能力。海豹的脾脏很大，相比之下人类的脾脏较小，但个体差异很大。与许多海洋哺乳动物不同，人类潜水员在很大程度上依赖肺部的氧气储备，但肺容量对竞技性屏气表现的影响尚未确定。我们研究了脾脏和肺的大小是否与精英屏气潜水员的表现相关。志愿者为14名男性屏气世界锦标赛参与者，之前屏气训练的平均（标准误）年限为5.8（1.2）年。通过超声在静息状态下测量脾脏的长度、宽度和厚度来计算脾脏体积，通过肺活量计测量肺活量。将最大深度、时间和距离潜水的累计比赛得分与人体测量数据和训练数据进行比较。平均（标准误）潜水表现为：恒重深度潜水75（4）米，静态屏气5分53（39）秒，动态屏气距离139（13）米。受试者的平均身高为184（2）厘米，体重82（3）千克，肺活量（VC）7.3（0.3）升，脾脏体积336（32）毫升。脾脏体积与受试者身高或体重无关，但与比赛得分呈正相关（r = 0.57；P < 0.05）。总比赛得分也与肺活量呈正相关（r = 0.54；P < 0.05）。得分最高的三名潜水员脾脏体积最大，平均为538（53）毫升，而得分最低的三名潜水员脾脏体积为270（71）毫升（P < 0.01）。高分者的肺活量也更大，为7.9（0.36）升，而低分者为6.7（0.19）升（P < 0.01）。得分最高的潜水员在屏气2分钟后脾脏体积减少到一半，高分者与低分者脾脏体积差异导致的估计静息屏气时间增加为15秒，肺活量差异导致的增加为60秒。我们得出结论，脾脏和肺的体积都可以预测精英潜水员的屏气表现。
