A quantitative approach for assessing significant improvements in elite sprint performance: Has IGF‐1 entered the arena?

Abstract

The introduction of doping substances and methods in sports triggers noticeable effects on physical performance in metric sports. Here, we use time series analysis to investigate the recent development in male and female elite sprinting performance. Time series displaying the average of the world's top 20 athletes were analyzed employing polynomial spline functions and moving averages. Outstanding changes in performance over time were statistically analyzed by Welch's t-test and by Cohen's measurements of effect. For validation we exemplarily show that our analysis is capable of indicating the effect of the introduction of in- and out-of-competition doping testing on women's shot put as well as the effects of the market introduction of erythropoietin (EPO) and the introduction of EPO and continuous erythropoiesis receptor activator (CERA) testing on 5000 m top 20 male performances. Time series analysis for 100 m men reveals a highly significant (p < 0.001) drop by more than 0.1 s from 2006 to 2011 with a large effect size of 0.952. This is roughly half of the effect size that can be found for the development of the 5000 m performance during the introduction of EPO between 1991 and 1996. While the men's 200 m sprinting performance shows a similar development, the women's 100 m and 200 m sprinting performances only show some minor abnormalities. We will discuss here why the striking sex-specific improvement in sprinting performance is indicative for a novel, very effective doping procedure with insulin-like growth factor-1 (IGF-1) being the primary candidate explaining the observed effects.

Prevalence of Doping Use in Elite Sports: A Review of Numbers and Methods

“…Pure statistical studies into the times of elite cyclists in various races failed to reach a clear conclusion [93,94], and this variability in factors that influence the final outcome of a race are most probably the reason to explain this ambiguity. Ernst and Simon speculated that recent improvements in sprinting performance in athletics could be indicative of a novel, very effective doping procedure (with insulin-like growth factor-1 being the primary candidate), but they also could not prove such assumptions [95].…”

Perception of the Current Anti-doping Regime – A Quantitative Study Among German Top-Level Cyclists and Track and Field Athletes

“…In spite of the official detection rate of around 1% many athletes still regard doping tests as a deterrent ( Waddington et al, 2005 ; Dunn et al, 2010 ; Overbye, 2016b ), whereby athletes with experience of testing within the past year were more likely to regard the likelihood of being selected for testing as a deterrent and only 40% of them found the risk of being selected for doping tests to be a deterrent ( Overbye, 2016a ). Using scenario analysis Strelan and Boeckmann (2006) show that doping testing has only a small influence on athletes’ drug use decisions.…”

Annual banned‐substance review: analytical approaches in human sports drug testing

“…The methodology was validated for quantitative purposes and the LOQ was 50 ng/mL, thus allowing the determination of IGF-1 at normal physiological concentrations as desirable for doping controls. In the absence of analytical proof, speculations as to the prevalence of IGF-1 as doping agent have arisen, particular with regard to elite sprinters, [99,100] and also deer antler velvet-derived nutritional supplements enriched with IGF-1 were recently reported. [101] In order to provide a platform for the generation of factual information on peptide hormone-based therapeutics and drug candidates, metabolism studies and method development/expansion for substances such as growth hormone releasing peptides (GHRPs, including GHRP-1, -2, -4, -5, and 6, as well as hexarelin, alexamorelin, and ipamorelin), luteinizing hormone releasing hormone (LHRH), and desmopressin were conducted.…”