Stride length and stride frequency in three stage of preperation of high level sprinters

Introduction

Results in sprint events (100-200 m run) depents on both stride length and stride frequency [1,2,3]. Previous works showed, that strid length and frequency depents on sex, body hight, sprint technique, level of motor preparation and preiod of training [1, 2, 3, 4]. The aim of this study was to find differences in both stride parameters in three periods of traning: general (in winter), special (in spring) and competition (in summer).

Methods

Nine best Polsih sprinters (100 m time, 10,25 (0,08s) s; body hight, 1,80 (0,08m), body weight, 74,1 (7,5kg) participated in this study. In three periods of preparation (Dec, Apr, Jul) they ran 60 m sprint from scratch start. Run time was measured by photocells. All runs was filmed by video camera. The stride length was estimated from numbers of strides and stride frequency was calculated from formula: number of strides / run time. Analysis of variance (ANOVA) was used to identify differences across stride length and frequency. Where ANOVA revealed significant at p ≤ 0,05, a post-hoc Tukey test was performed. Values in the text are reported as mean (standard deviation).

Results

There is statistically significantly differentes between stride frequency (F =6,09, p ≤ 01) and running velocity (F = 28,90, p ≤ 01) in three periods of training. The stride length was constants from winter to summer (F = 1,03) (table 1). Running velocity of sprinters depends on stride frequency (specially in winter and summer) and stride length (table 2).

Table 1. Velocity of running, stride length and stride frequency in three periods of preparation.

Parameter/Mont	Dec	Apr	Jun	F
Velocity of running (m/s)	8.73 (0,10)	8.88 (0,10)	9.11 (0,13)	28,90b
Stride length (m)	2.11 (0,10)	2.04 (0,10)	2.07 (0,09)	1,03
Stride frequency (1/m)	4.14 (0,13)	4.35 (0,18)	4.40 (0,18)	6,09a

a - p ≤ 0,05,
b - p ≤ 0.1

Table 2. Coefficient of correlation between velocity of running and stride parameters

Parameter/Month	Dec	Apr	Jun
Stride length	0,24	0,67a	0,70a
Stride frequenc	0,89b	0,53	0,91b

a - r significant at p ≤ 05,
b - p ≤ 01

Discussion/Conclusions

In all sprint training periods we must concentrated on development both stride frequency and stride length [1]. In competition periods (indoor and outdoor) speed frequency determines efficiency of sprint training. In April (special preparation period) sprinters concentrated on development of stride length.

References

1. Ballreich R. & Gabel H. (1975). Leistungssport 5, 346-351.
   
2. Dintiman G.B. &Ward R.D. (1988). Sport speed. Champaign, Leisure Press.
   
3. Donati A. (1995). New Stud. In Athletics, 1, 51-66.
   
4. Mero et al. (1992). Sport Medicine, 6, 376-392.