Data on hemodynamic variables and doses of vasoactive agents are shown in Figure 3 and Figure 4 in the Supplementary Appendix. The mean arterial pressure was similar in the two treatment groups at baseline, and it changed similarly over time, although it was slightly higher from 12 to 24 hours in the norepinephrine group. The doses of the study drug were similar in the two groups at all times. More patients in the dopamine group than in the norepinephrine group required open-label norepinephrine therapy at some point (26% vs. 20%, P<0.001), but the doses of open-label norepinephrine that were administered were similar in the two groups. The use of open-label epinephrine at any time was similar in the two groups (administered in 3.5% of patients in the dopamine group and in 2.3% of those in the norepinephrine group, P=0.10), as was the use of vasopressin (0.2% in both groups, P=0.67). Dobutamine was used more frequently in patients treated with norepinephrine, but 12 hours after randomization, the doses of dobutamine were significantly higher in patients treated with dopamine. The mean (±SD) time to the achievement of a mean arterial pressure of 65 mm Hg was similar in the two groups (6.3±5.6 hours in the dopamine group and 6.0±4.9 hours in the norepinephrine group, P=0.35). There were no major between-group differences in the total amounts of fluid given, although patients in the dopamine group received more fluids on day 1 than did patients in the norepinephrine group. Urine output was significantly higher during the first 24 hours after randomization among patients in the dopamine group than among those in the norepinephrine group, but this difference eventually disappeared, so that the fluid balance was quite similar between the two groups.
When tendons elongate to a greater extent during a jumping movement that is preceded by a countermovement, the muscle lengthens less. This produces two effects. Firstly, the greater elongation of the tendon means that more elastic energy is stored during the countermovement, which is then released in the subsequent jumping phase. Secondly, the smaller elongation of the muscle means that countermovement depth can be greater for the same shortening velocity in the subsequent jumping phase, because the muscle never lengthened that much to begin with. Since shortening velocity determines force, this allows the same muscle force to be produced, despite the larger joint range of motion.

After four months of failing to pull off anything even resembling a real dunk, the planets aligned on Aug. 9: After at least 19 failed attempts that afternoon, I dunked a soccer ball on a middle school court whose rim measured 9' 11". (The original basketball, incidentally, was a soccer ball, property of Dr. Naismith’s employer, Springfield College.) Video from that afternoon shows me standing there, looking confused, in the moment afterward. Did that just happen? Failing had become so routine that even this small success felt foreign.


The method described above is the most common and simplest way to measure one's vertical jump, but other more scientifically accurate methods have been devised. A pressure pad can be used to measure the time it takes for an athlete to complete a jump, and then using a kinematics equation (h = g × t2/8),[4] the computer can calculate his or her vertical jump based on the time in the air.
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