Author(s): GUO, Q., YUAN, T., Institution: CHINA INSTITUTE OF SPORT SCIENCE, Country: CHINA, Abstract-ID: 2234

INTRODUCTION:
Resistance running(RS) is widely recognized as the most commonly used and effective method to enhance speed performance and overcome speed barriers in sprint training. Some studies have employed body mass (bm) as a benchmark, revealing that varying percentages of body mass as resistance yield different training effects. For instance, 12.5%bm RS enhances high-speed acceleration phases. Another study utilized 10%bm, 30%bm, and 50%bm for resistance running training, suggesting that faster and stronger athletes may require relatively heavier resistance to attain their training goals. This study investigates resistance ranging from 1% to 10%bm, aiming to determine if athletes with different physical characteristics benefit from personalized resistance for achieving specific training goals within this range.
METHODS:
Twenty-nine elite track and field athletes participated in this study, comprising 18 male and 11 female athletes. All athletes underwent the same warm-up procedure, followed by a squat 1RM test and a 30m sprint test without resistance （T-133 timing system，eliga，china）on the same day. Within one week of the initial test, the athletes engaged in resistance running training（T120-sprint training device，eliga，china）. The resistance was set between 1%-10% of the athletes body weight(bw), and the 30m times were recorded, above test excluding reaction time. Linear regression analysis was conducted using SPSS software to assess the impact of gender, weight, and relative strength (squat 1RM/body weight) on the rate of speed decline.
RESULTS:
The average time for the 30m sprint without resistance was recorded at 3.835 seconds, with a standard deviation of 0.123 seconds. The average relative strength was measured at 2.100, with a standard deviation of 0.251, and the average rate of speed decline was found to be 15.37%, with a standard deviation of 3.613%. For female athletes, the average 30m sprint time was 4.087 seconds, with a standard deviation of 0.133 seconds; the average relative strength was 1.818, with a standard deviation of 0.217; and the average rate of speed decline was 21.281%, with a standard deviation of 6.679%.Linear regression analysis revealed that resistance as a percentage of body weight, within the range of 1%-10% (B=1.635, p<0.01), and gender (B=0.079, p<0.01) significantly influenced the rate of speed decline. However, relative strength (B=-0.048, p=0.144) and the finish time for the sprint without resistance (B=-0.110, p=0.074) did not show a significant effect on the rate of speed decline.
CONCLUSION:
The findings of this study indicate that in resistance running training, when the load is below 10% of body weight (bw), the trend of speed decline is roughly similar across athletes of different strength levels as resistance increases. However, gender and the amount of load are significant factors affecting the rate of speed decline, with female athletes experiencing a slightly higher rate of decline compared to male athletes. This suggests that when des