Akademik Veri Yönetim Sistemi
13. Uluslararası Spor bilimleri kongresi, Konya, Türkiye, 7 - 09 Kasım 2014, (Özet Bildiri)
Abstract
Introduction and Purpose: Many athletes perform various stretching exercises as a part of a warmup
prior to physical activity and sports competition in order to enhance athletic performance and
prevent injuries. However, in the literature; there is not enough information about the effects of
stretching techniques on athletic performance and the results of several previous studies are conflicting
on the benefits and disadvantages of the different stretching techniques. The purpose of this study was
to investigate the effects of static and PNF stretching techniques on peak power, average power and
fatigue index.
Materials and Methods: Fifteen active male athletes whose age, stature, body mass and body fat
percentage are 20,20±2,75year, 176,±7,46cm, 69,23±5,38kg and 12,22±2,60%, respectively were
participated in this study as volunteers. Randomized cross-over experimental design was used in in
this study. The athletes were participated in static stretching (SS), proprioceptive neuromuscular
facilitation (PNF) and no stretching (baseline) applications in randomized manner with a two day
intervals between trials. Stretching exercises were applied to hamstrings, quadriceps and calf muscles
for both legs following five minutes standard warm-up. SS application was performed 3x30sec on
each muscle group, with 10 seconds resting intervals between sets. PNF exercise was performed in
three stages. In the first stage 10 seconds passive stretching was performed by the researcher until the
subject feels pain on his muscle. In the second stage the subject applied resistance against the
stretching pressure of the researcher, for 6 seconds. In the last stage again passive stretching was
applied by the researcher for 14 seconds. Same as in the SS, each set of PNF application was taken
totally 30 seconds and this application was repeated three sets with 10 seconds resting intervals, for
each muscle group. All stretching exercises were applied by the same experienced researcher, to the
both legs of the subject. In control trials (baseline), subjects were directly started to anaerobic test after
a five minutes standard warm-up period without applying any stretching exercises. After stretching
exercise protocols, Wingate 30 sec anaerobic test (WAnT) was conducted for the evaluation of
anaerobic performance. Maximum peak power, average power and fatigue index was determined by
WAnT. Repeated measures of ANOVA was used for statistical analyzes.
Results: According to repeated measures of one way ANOVA significant difference (F (2-28) = 6,771;
P=0,004) was determined between trials regarding to peak power values. After the follow up test,
significant differences was identified between PNF (12.70 W/kg) and SS (12.07 W/kg) trials, in favor
of PNF. There was no significant differences between stretching trials regarding to average power (F
(2-28) =0,639; P=0,535) and fatigue index (F (2-28) =0,56, P=0,577).
Conclusions: As a result, SS applications following warm-up periods leads to loss of athletic
performance which requires explosive power efforts. On the other hand, PNF stretching applications
do not cause any performance loss. It is concluded that, PNF type of exercises are more appropriate
when stretching exercises are needed following warm-up periods, especially in the sports which
require short term explosive power.
Keywords: Static Stretching, Pnf, Peak Power, Average Power, Fatique Index