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Effects of Sled Towing on Peak Force, the Rate of Force Development and Sprint Performance During the Acceleration Phase.

Martínez-Valencia MA, Romero-Arenas S, Elvira JL, González-Ravé JM, Navarro-Valdivielso F, Alcaraz PE - J Hum Kinet (2015)

Bottom Line: Repeated-measures ANOVA showed significant increases (p ≤ 0.001) in sprint times (20 and 30 m sprint) for each resisted condition as compared to the unloaded condition.The RFDpeak increased significantly when a load increased (3129.4 ± 894.6 N·s-1, p ≤ 0.05 and 3892.4 ± 1377.9 N·s-1, p ≤ 0.01).Otherwise, no significant increases were found in Fpeak and TRFD.

View Article: PubMed Central - PubMed

Affiliation: UCAM Research Center of High Performance Sport, San Antonio Catholic University of Murcia, Guadalupe, Murcia, Spain.

ABSTRACT
Resisted sprint training is believed to increase strength specific to sprinting. Therefore, the knowledge of force output in these tasks is essential. The aim of this study was to analyze the effect of sled towing (10%, 15% and 20% of body mass (Bm)) on sprint performance and force production during the acceleration phase. Twenty-three young experienced sprinters (17 men and 6 women; men = 17.9 ± 3.3 years, 1.79 ± 0.06 m and 69.4 ± 6.1 kg; women = 17.2 ± 1.7 years, 1.65 ± 0.04 m and 56.6 ± 2.3 kg) performed four 30 m sprints from a crouch start. Sprint times in 20 and 30 m sprint, peak force (Fpeak), a peak rate of force development (RFDpeak) and time to RFD (TRFD) in first step were recorded. Repeated-measures ANOVA showed significant increases (p ≤ 0.001) in sprint times (20 and 30 m sprint) for each resisted condition as compared to the unloaded condition. The RFDpeak increased significantly when a load increased (3129.4 ± 894.6 N·s-1, p ≤ 0.05 and 3892.4 ± 1377.9 N·s-1, p ≤ 0.01). Otherwise, no significant increases were found in Fpeak and TRFD. The RFD determines the force that can be generated in the early phase of muscle contraction, and it has been considered a factor that influences performance of force-velocity tasks. The use of a load up to 20% Bm might provide a training stimulus in young sprinters to improve the RFDpeak during the sprint start, and thus, early acceleration.

No MeSH data available.


Related in: MedlinePlus

Load cell placement
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f1-jhk-46-139: Load cell placement

Mentions: Data were collected in one session. The sprint trials were conducted on an outdoor synthetic track. Testing was carried out during the pre-season phase of athlete’s training when the athletes were following maximal strength, resisted, acceleration, and maximum-velocity sprint training. The training program consisted of four sessions, and two maximal strength training sessions per week. Anthropometric information was collected prior to the warm-up. Body height and mass (Seca780, Vogel & Halke, Germany) were measured before starting the sprint trials to determine the loads relative to 10%, 15% and 20% Bm. Afterwards, the participants performed a specific warm-up consisting of 8 min of running, 8 min of active stretching, 10 min of running technique exercises, and 2–4 submaximal and maximal short sprints. The sprint trials were performed using a 4.7 kg weighted sled (Power Systems Inc., Knoxville, TN) attached to each athlete by a 3.6 m cord and waist harness. A load cell (MuscleLab, Ergotest Innovation, Norway) was attached between the waist harness and the cord (Figure 1). The load cell was calibrated by the use of standard loads and the signal analysis software (Musclelab 4000e, Ergotest Innovation). Participants wore their own athletic training clothes and spiked sprint shoes.


Effects of Sled Towing on Peak Force, the Rate of Force Development and Sprint Performance During the Acceleration Phase.

Martínez-Valencia MA, Romero-Arenas S, Elvira JL, González-Ravé JM, Navarro-Valdivielso F, Alcaraz PE - J Hum Kinet (2015)

Load cell placement
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4519204&req=5

f1-jhk-46-139: Load cell placement
Mentions: Data were collected in one session. The sprint trials were conducted on an outdoor synthetic track. Testing was carried out during the pre-season phase of athlete’s training when the athletes were following maximal strength, resisted, acceleration, and maximum-velocity sprint training. The training program consisted of four sessions, and two maximal strength training sessions per week. Anthropometric information was collected prior to the warm-up. Body height and mass (Seca780, Vogel & Halke, Germany) were measured before starting the sprint trials to determine the loads relative to 10%, 15% and 20% Bm. Afterwards, the participants performed a specific warm-up consisting of 8 min of running, 8 min of active stretching, 10 min of running technique exercises, and 2–4 submaximal and maximal short sprints. The sprint trials were performed using a 4.7 kg weighted sled (Power Systems Inc., Knoxville, TN) attached to each athlete by a 3.6 m cord and waist harness. A load cell (MuscleLab, Ergotest Innovation, Norway) was attached between the waist harness and the cord (Figure 1). The load cell was calibrated by the use of standard loads and the signal analysis software (Musclelab 4000e, Ergotest Innovation). Participants wore their own athletic training clothes and spiked sprint shoes.

Bottom Line: Repeated-measures ANOVA showed significant increases (p ≤ 0.001) in sprint times (20 and 30 m sprint) for each resisted condition as compared to the unloaded condition.The RFDpeak increased significantly when a load increased (3129.4 ± 894.6 N·s-1, p ≤ 0.05 and 3892.4 ± 1377.9 N·s-1, p ≤ 0.01).Otherwise, no significant increases were found in Fpeak and TRFD.

View Article: PubMed Central - PubMed

Affiliation: UCAM Research Center of High Performance Sport, San Antonio Catholic University of Murcia, Guadalupe, Murcia, Spain.

ABSTRACT
Resisted sprint training is believed to increase strength specific to sprinting. Therefore, the knowledge of force output in these tasks is essential. The aim of this study was to analyze the effect of sled towing (10%, 15% and 20% of body mass (Bm)) on sprint performance and force production during the acceleration phase. Twenty-three young experienced sprinters (17 men and 6 women; men = 17.9 ± 3.3 years, 1.79 ± 0.06 m and 69.4 ± 6.1 kg; women = 17.2 ± 1.7 years, 1.65 ± 0.04 m and 56.6 ± 2.3 kg) performed four 30 m sprints from a crouch start. Sprint times in 20 and 30 m sprint, peak force (Fpeak), a peak rate of force development (RFDpeak) and time to RFD (TRFD) in first step were recorded. Repeated-measures ANOVA showed significant increases (p ≤ 0.001) in sprint times (20 and 30 m sprint) for each resisted condition as compared to the unloaded condition. The RFDpeak increased significantly when a load increased (3129.4 ± 894.6 N·s-1, p ≤ 0.05 and 3892.4 ± 1377.9 N·s-1, p ≤ 0.01). Otherwise, no significant increases were found in Fpeak and TRFD. The RFD determines the force that can be generated in the early phase of muscle contraction, and it has been considered a factor that influences performance of force-velocity tasks. The use of a load up to 20% Bm might provide a training stimulus in young sprinters to improve the RFDpeak during the sprint start, and thus, early acceleration.

No MeSH data available.


Related in: MedlinePlus