Physiological and Locomotor Profiling Enables to Differentiate Between Sprinters, 400-m Runners, and Middle-Distance Runners.

ABSTRACT: Thron, M, Woll, A, Doller, L, Quittmann, OJ, Härtel, S, Ruf, L, and Altmann, S. Physiological and locomotor profiling enables to differentiate between sprinters, 400-m runners, and middle-distance runners. J Strength Cond Res XX(X): 000-000, 2024-Different approaches exist for characterizing athletes, e.g., physiological and locomotor profiling. The aims of this study were to generate and compare physiological and locomotor profiles of male and female runners and to evaluate relationships between the different approaches. Thirty-four highly trained adolescent and young adult female and male athletes (n = 11 sprinters; n = 11,400-m runners; n = 12 middle-distance runners) performed two 100-m sprints on a running track to determine maximal sprinting speed (MSS) and maximal lactate accumulation rate (cLamax). A cardiopulmonary exercise test was performed on a treadmill to determine maximal aerobic speed (MAS) and maximal oxygen uptake (V̇o2max). Anaerobic speed reserve (ASR) was calculated as the difference between MSS and MAS. Group comparisons were conducted with a 2-way ANOVA (discipline × sex; p < 0.05) and Bonferroni post hoc tests and Cohen's d as effect size. Parameters were correlated by Pearson's correlation coefficients. Maximal aerobic speed and V̇o2max were higher in 400-m and middle-distance runners compared with sprinters (p ≤ 0.02; -2.24 ≤ d ≤ -1.29). Maximal sprinting speed and cLamax were higher in sprinters and 400-m runners compared with middle-distance runners (0.03 ≤ p ≤ 0.28; 0.73 ≤ d ≤ 1.23). Anaerobic speed reserve was highest in sprinters and lowest in middle-distance runners (p ≤ 0.03; 1.24 ≤ d ≤ 2.79). High correlations were found between ASR and MAS, MSS, and cLamax (p < 0.01; -0.55 ≤ r ≤ 0.91) and between cLamax and MSS (p < 0.01; r = 0.74). Our results indicate that athletes of different sprinting and running disciplines show differing physiological and locomotor profiles, and that the parameters of these approaches are related to each other. This can be of interest for assessing strengths and weaknesses (e.g., for talent identification) or training prescription in these disciplines.

Data Processing Strategies to Determine Maximum Oxygen Uptake: A Systematic Scoping Review and Experimental Comparison with Guidelines for Reporting.

BACKGROUND: Gas exchange data from maximum oxygen uptake ([Formula: see text]) testing typically require post-processing. Different processing strategies may lead to varying [Formula: see text] values affecting their interpretation. However, the exact processing strategies used in the literature have yet to be systematically investigated. Previous research investigated differences across methods at the group level only. METHODS: Out of a random sample, we investigated 242 recently published articles that measured [Formula: see text] during ramp tests. Reported data processing methods and their rationale were extracted. We compared the most common processing strategies on a data set of 72 standardized exercise tests in trained athletes. RESULTS: Half of the included studies did not report their data processing strategy and almost all articles failed to provide a rationale for the particular strategy chosen. Most studies use binned time averages to determine [Formula: see text], with a minority using moving time or moving breath averages. The processing strategies found in the literature can lead to mean differences in [Formula: see text] of more than 5% (range 0-7%) with considerable variation at the individual level. CONCLUSIONS: We advise researchers to change their processing strategy and use moving averages or digital filters instead of binned averages. Researchers should report their data processing strategy used to determine [Formula: see text]. We provide a reporting checklist of seven items that can function as a template for reporting.

Is Maximal Lactate Accumulation Rate Promising for Improving 5000-m Prediction in Running?

Endurance running performance can be predicted by maximal oxygen uptake (V̇O2max), the fractional utilisation of oxygen uptake (%V̇O2max) and running economy at lactate threshold (REOBLA). This study aims to assess maximal lactate accumulation rate (cLamax) in terms of improving running performance prediction in trained athletes. Forty-four competitive female and male runners/triathletes performed an incremental step test, a 100-m sprint test and a ramp test to determine their metabolic profile. Stepwise linear regression was used to predict 5000-m time trial performance. Split times were recorded every 200-m to examine the 'finishing kick'. Females had a slower t5k and a lower V̇O2max, cLamax, 'finishing kick' and REOBLA. Augmenting Joyner's model by means of cLamax explained an additional 4.4% of variance in performance. When performing the same analysis exclusively for males, cLamax was not included. cLamax significantly correlated with %V̇O2max (r=-0.439, p=0.003) and the 'finishing kick' (r=0.389, p=0.010). cLamax allows for significant (yet minor) improvements in 5000-m performance prediction in a mixed-sex group. This margin of improvement might differ in middle-distance events. Due to the relationship to the 'finishing kick', cLamax might be related to individual pacing strategies, which should be assessed in future research.

Maximal Lactate Accumulation Rate in All-out Exercise Differs between Cycling and Running.

This study aims to compare maximal lactate accumulation rate (V̇ Lamax) and power output (Pmax) between cycling and running in terms of reliability, differences between, and correlations among modalities. Eighteen competitive triathletes performed a 15-s all-out exercise test in cycling and a 100-m sprint test in running. Each test was performed twice and separated by one week. Exercise tests in cycling were performed on an ergometer whereas sprint tests in running were performed on an indoor track. Differences between trials and exercise modality were analyzed using two-way ANOVA. V̇ Lamax (ICC=0.894, ICC=0.868) and Pmax (ICC=0.907, ICC=0.965) attained 'good' to 'excellent' reliability in both cycling and running, respectively. V̇ Lamax was higher in running (d=0.709, p=0.016) whereas Pmax was lower in running (d=-0.862, p < 0.001). For V̇ Lamax, limits of agreement between modalities ranged from -0.224 to +0.437 mmol·l-1·s-1. Pmax correlated between modalities (r=0.811, p < 0.001), whereas no correlation was found in V̇ Lamax (r=0.418, p=0.084). V̇ Lamax is highly reliable in both modalities and higher in running compared to cycling. Since V̇ Lamax does not correlate between cycling and running, it should be determined sport-specifically.

Comparison of Different Blood Lactate Threshold Concepts for Constant Load Performance Prediction in Spinal Cord Injured Handcyclists.

BACKGROUND: Endurance capacity is one of the main performance determinants in handcycling. There are two exercise test procedures primarily applied to determine endurance capacity, to verify training adaptations and predict race performance. This study aims to evaluate the agreement of these applied concepts in handcycling. METHODS: In a repeated measures cross-over design, 11 highly trained male spinal cord injured (Th12 to L1) handcyclists (age: 40 ± 9 years, height: 183 ± 8 cm, body mass: 73.2 ± 8.5 kg) performed a graded exercise test (GXT) and a lactate minimum test (LMT) to determine lactate threshold at 4 mmol L-1 (LT4 mmol L-1) and lactate minimum (LM), respectively. The agreement of both lactate thresholds concepts for constant load performance prediction (change of ≤ 1 mmol L-1 during the last 20 min) was evaluated within constant load tests (CLT; 30 min) at a power output (PO) corresponding to LT4 mmol L - 1 and LM. Oxygen uptake ( V . ⁢ O 2 ), respiratory exchange ratio (RER), heart rate (HR) and blood lactate (La) were measured during all tests. RESULTS: Power output at the corresponding thresholds (LT4 mmol L-1: 149 ± 34 W vs. LM: 137 ± 18 W) revealed no significant difference (p = 0.06). During the CLT at LT4 mmol ⋅ L -1 and LM, V . ⁢ O 2 , and RPE were not significantly different. However, LA, RER, and HR were significantly higher (p ≤ 0.02) during CLT at LT4 mmol L-1. Bland-Altman plots indicate a wide range of dispersion for all parameters between both lactate threshold concepts. Evaluations of LT4 mmol L-1 and LM did not meet the criteria for constant load performance within the CLT for 33 and 17% of the athletes, respectively. DISCUSSION: Both exercise tests and the corresponding lactate threshold concept revealed appropriate estimates to predict a steady state performance for the majority of participants. However, as PO determination at LT4 mmol L-1 and LM exceeds the criteria for constant load performance (increase of ≥ 1 mmol L-1) for 33 and 17% respectively the current results indicate the common criteria for constant load performance (change of ± 1 mmol L-1) might not be sufficiently precise for elite athletes in handcycling. Consequently, exercise test results of elite athletes should be analyzed individually and verified by means of several CLT.

The Effect of Block Versus Daily Undulating Periodization on Strength and Performance in Adolescent Football Players.

Purpose: Muscle mass, strength, and power are important factors for performance. To improve these characteristics, periodized resistance training is used. However, there is no consensus regarding the most effective periodization model. Therefore, the purpose of this study was to compare the effects of block (BLOCK) vs daily undulating periodization (DUP) on body composition, hypertrophy, strength, performance, and power in adolescent American football players. Methods: A total of 47 subjects participated in this study (mean [SD] age = 17 [0.8] y, strength training experience = 0.93 [0.99] y). Premeasurements and postmeasurements consisted of body mass (BM); fat mass; relative fat mass; fat-free mass (FFM); muscle mass (MM); muscle thickness of the vastus lateralis (VL), rectus femoris (RF), and triceps brachii (TB); 1-repetition-maximum back squat (BS) and bench press (BP); countermovement jump (CMJ); estimated peak power (Wpeak) from vertical jump performance; medicine-ball put (MBP); and 40-yd sprint. Subjects were randomly assigned in either the BLOCK or DUP group prior to the 12-wk intervention period consisting of 3 full-body sessions per week. Results: Both groups displayed significantly higher BM (P < .001), FFM (P < .001), MM (P < .001), RF (P < .001), VL (P < .001), TB (P < .001), BS (P < .001), BP (P < .001), CMJ (P < .001), Wpeak (P < .001), and MBP (P < .001) and significantly lower sprint times (P < .001) after 12 wk of resistance training, with no difference between groups. Conclusions: Resistance training was effective to increase muscle mass, strength, power, and performance in adolescent athletes. BLOCK and DUP affect anthropometric measures and physical performance equally.