[הזברה]

טוב, קראתי הכל ויש שני מחקרים שאולי מענינים קצת יותר:

The effect of static, ballistic, and proprioceptive neuromuscular facilitation stretching on vertical jump performance.

Bradley PS, Olsen PD, Portas MD.
Sport and Exercise Group, University of Teesside, UK. paul.s.bradley@sunderland.ac.uk
The purpose of this study was to compare the acute effects of different modes of stretching on vertical jump performance. Eighteen male university students (age, 24.3 +/- 3.2 years; height, 181.5 +/- 11.4 cm; body mass, 78.1 +/- 6.4 kg; mean +/- SD) completed 4 different conditions in a randomized order, on different days, interspersed by a minimum of 72 hours of rest. Each session consisted of a standard 5-minute cycle warm-up, accompanied by one of the subsequent conditions: (a) control, (b) 10-minute static stretching, (c) 10-minute ballistic stretching, or (d) 10-minute proprioceptive neuromuscular facilitation (PNF) stretching. The subjects performed 3 trials of static and countermovement jumps prior to stretching and poststretching at 5, 15, 30, 45, and 60 minutes. Vertical jump height decreased after static and PNF stretching (4.0% and 5.1%, p < 0.05) and there was a smaller decrease after ballistic stretching (2.7%, p > 0.05). However, jumping performance had fully recovered 15 minutes after all stretching conditions. In conclusion, vertical jump performance is diminished for 15 minutes if performed after static or PNF stretching, whereas ballistic stretching has little effect on jumping performance. Consequently, PNF or static stretching should not be performed immediately prior to an explosive athletic movement.
PMID: 17313299 [PubMed - indexed for MEDLINE]

Effects of six warm-up protocols on sprint and jump performance.

Vetter RE.
Health, Physical Education, Recreation, and Dance Department, Northwest Missouri State University, Maryville, Missouri 64468, USA. rvetter@nwmissouri.edu
The purpose of this study was to compare the effects of 6 warm-up protocols, with and without stretches, on 2 different power maneuvers: a 30-m sprint run and a vertical countermovement jump (CJ). The 6 protocols were: (a) walk plus run (WR); (b) WR plus exercises including small jumps (EJ); (c) WR plus dynamic active stretch plus exercises with small jumps (DAEJ); (d) WR plus dynamic active stretch (DA); (e) WR plus static stretch plus exercises with small jumps (SSEJ); and (f) WR plus static stretch (SS). Twenty-six college-age men (n = 14) and women (n = 12) performed each of 6 randomly ordered exercise routines prior to randomly ordered sprint and vertical jump field tests; each routine and subsequent tests were performed on separate days. A 2 x 6 repeated measures analysis of variance revealed a significant overall linear trend (p < or = 0.05) with a general tendency toward reduction in jump height when examined in the following analysis entry order: WR, EJ, DAEJ, DA, SSEJ, and SS. The post hoc analysis pairwise comparisons showed the WR protocol produced higher jumps than did SS (p = 0.003 < or = 0.05), and DAEJ produced higher jumps than did SS (p = 0.009 < or = 0.05). There were no significant differences among the 6 protocols on sprint run performance (p > or = 0.05). No significant interaction occurred between gender and protocol. There were significant differences between men and women on CJ and sprint trials; as expected, in general men ran faster and jumped higher than the women did. The data indicate that a warm-up including static stretching may negatively impact jump performance, but not sprint time.
PMID: 17685698 [PubMed - in process]

לפי הראשון ,הניתור נפגע ממתיחות PNF ומתיחות סטטיות ופחות אחרי מתיחות דינמיות.
לפי השני:
A 2 x 6 repeated measures analysis of variance revealed a significant overall linear trend (p < or = 0.05) with a general tendency toward reduction in jump height when examined in the following analysis entry order: WR, EJ, DAEJ, DA, SSEJ, and SS

כלומר ,גם מתיחות דינמיות פוגעות בביצוע ,יחסית לחימום ספציפי והניחוש שלי הוא שבגלל שבקפיצה יש שלב שבו השריר נמתח מעט בנחיתה ,אז הקפיצה עצמה היתה פחות יעילה כחימום מהריצה לבד.
מסקנה: מי שאומר שצריך להתחמם עם מתיחות דינמיות כנראה טועה.