And meanwhile, those calcium pumps are working hard to restock the calcium in the sarcoplasmic reticulum.

与此同时，这些钙泵正在努力补充肌浆网中钙。

Its walls are loaded with calcium pumps — which use ATP to save up a bunch of calcium ions.

上装有钙泵——三磷酸腺苷来储存一堆钙离子。

That tension means myosin and the calcium pumps are burning up the muscle cells' ATP, and the finite supply of ATP is what makes it impossible to maintain vigorous muscle activity indefinitely.

这种张力意味着肌球蛋白和钙泵正在燃烧肌肉细胞三磷酸腺苷，而三磷酸腺苷有限供应得肌肉活动不可能无限期地保持旺盛。