EFFECT OF SHORT BURST ACTIVITIES ON SPRINT AND AGILITY PERFORMANCE IN 11- TO 12-YEAR-OLD BOYS SVEIN A. PETTERSEN 1 AND GUNNAR E. MATHISEN 2 1 The Regional Center for Sport, Exercise and Health–North and 2 Faculty of Humanities, Social Sciences and Education, University of Tromsoe, Tromsoe, Norway ABSTRACT Pettersen, SA and Mathisen, GE. Effect of short burst activities on sprint and agility performance in 11- to 12-year-old boys. J Strength Cond Res 26(4): 1033–1038, 2012—There are limited data on how coordinative sprint drills and maximal short burst activities affects children’s sprint and agility performance. The purpose of the present study was to investigate the effect of short burst activities on sprint and agility performance in 11- to 12-year-old boys. A training group (TG) of 14 boys followed a 6-week, 1-hourÁweek 21 , training program consisting of different short burst competitive sprinting activities. Eleven boys of similar age served as controls (control group [CG]). Pre- and posttests assessed 10-m sprint, 20-m sprint, and agility performance. Results revealed significant performance improvement in all tests within TG (p , 0.05), but not between TG and CG in the 10-m sprint test. Furthermore, the relationships between the perform- ances in straight-line sprint and agility showed a significant transfer effect (r = 0.68–0.75, p , 0.001). Findings from the present study indicate that competitive short burst activities executed with maximal effort may produce improvement in sprint and agility performance in 11- to 12-year-old boys. KEY WORDS acceleration, sprint training, children, agility testing INTRODUCTION D uring the course of development in childhood years, strength, motor skills, and running speed improve (23). The issue of trainability in children has been related primarily to the effects of regular training on the development of aerobic power (1,4,11,16,18,24,27). There are some training studies on adaptability of anaerobic exercise capacity in growing children and adolescents, generally resulting in small increments in performance (2). Most studies have used power production in short-burst activities, conducting Wingate anaerobic power test (30-seconds all-out maximal effort on a cycle ergometer), with peak power (watts) and 30-second anaerobic capacity (kilojoules) as outcome measures (22). There are limited data on how sprint training regimens or sprint and agility drills affect children’s sprint and agility performance (23). Mosher et al. (18) reported 20% increase in high-intensity treadmill running in 10- to 11-year- old soccer players after 12 weeks of high-speed activity training. Interestingly there were no changes in 40-yd sprint times. Kotzamanidis (13) showed that a 10-week, twice-per- week, plyometric training program resulted in significantly increased 20- and 30-m sprint velocity, but not 10-m sprint velocity in 11-year-old boys compared with a control group (CG) of similar age. Buchheit et al. (3) found that 10-week, 1-hourÁweek 21 , repeated shuttle sprints and explosive strength training pro- duced significant improvement in 30-m sprint, but no significant improvement in 10-m sprint in adolescent male elite soccer players. From the existing collection of information, Rowland (p. 207) (23) concludes that it is impossible to say whether children are trainable in short burst activities. In adults, straight-line speed and agility, the ability to move quickly and change direction while maintaining control and balance (19), have been found to be independent qualities that are specific and produce limited transfer to each other (14,28). Whether children are in line with adults regarding these qualities are not well known. Both understanding the meaning of and being motivated to work at maximal intensity can be challenging for children. By using competitive activities, you can create more attractive conditions and enhanced motivation and thereby provoke maximal effort in short sprints for this age group (15). Thus, the main purpose of this study was to investigate the effect of competitive sprint activities, 1-hourÁweek 21 for 6 weeks, on sprint and agility performance in 11- to 12-year- old boys. It is our hypothesis that short straight-line speed and agility performance is trainable and that the stimulation is highly specific to its outcome, in 11- to 12-year-old boys. A key factor is a sufficient intensity level; it means maximal Address correspondence to Svein A. Pettersen, svein.arne.pettersen@uit.no. 26(4)/1033–1038 Journal of Strength and Conditioning Research Ó 2012 National Strength and Conditioning Association VOLUME 26 | NUMBER 4 | APRIL 2012 | 1033 Copyright © National Strength and Conditioning Association Unauthorized reproduction of this article is prohibited.