ECSS Paris 2023: OP-AP37
INTRODUCTION: Pole vault is a sport highly determined by run-up velocity, allowing maximal energy transfer to the pole (1). Vertical jump force plate-derived variables are associated with sprint performance (2). The horizontal force-velocity (FV) profile describes how athletes develop acceleration and velocity. This profile can be used to individualise and optimise sport training (3). The aim of this study was to explore relationships between CMJ, FV profile, sprint performance and personal best (PB) in pole vaulters, and to investigate sex differences. METHODS: Twenty-four pole vaulters with a minimum of two years of experience (11 women and 13 men), aged 15.61±2.65 years, body mass 56.98±10.95 kg, participated in the study. PB was 3.10±0.39 m and 3.70±0.57 m for women and men, respectively. All data were measured in the same session before the competitive period. Participants performed three CMJs after familiarisation on a CCAthletics force platform. Afterwards, they performed two trials of a 30 m sprint using a Racenanalyzer (Chronojump, Boscosystem). For the CMJ, participants were instructed to jump as high as possible after a period of stabilisation, during which body weight was measured. For the 30 m run, participants were instructed to run as fast as possible, and the FV profile was calculated using Chronojump software (v2.5.2) following the method described in (4). The best CMJ (jump height measured by impulse) and best 30 m time were analysed using JASP (v0.95.4, University of Amsterdam). Descriptive statistics and Pearson correlation analyses were performed between CMJ variables, FV profile key variables and participant's PB. RESULTS: Multiple CMJ-derived force and power variables showed moderate to very large correlations with PB in the male sample (r=0.72–0.92), whereas no significant relationships were found in the female sample. Sprint split times (10 m, 20 m and 30 m) showed stronger associations with PB in males compared with females. V0 and Vmax variables of the FV profile were also correlated with multiple CMJ-derived variables, particularly in the male sample. CONCLUSION: CMJ force plate-derived variables and FV profile are useful tools for assessing performance and monitoring training adaptation in pole vaulters as previously reported in the literature for sprinters (1,3). However, male and female athletes should be analysed separately. In males, velocity and power appear to be key determinants of performance, whereas this was not observed in the female sample. These findings suggest that performance improvement in female athletes may depend on additional factors not captured by CMJ or FV profile assessments. Further research across different performance levels and age groups is required to determine the main performance determinants and to optimise training monitoring strategies for coaches. 1.Gross et al. J Strength Cond Res 2020. 2.Loturco et al. Sports 2018. 3.Morin & Samozino. Int J Sports Physiol Perform 2015. 4.Samozino et al. Med Sci Sports Exerc 2013.
Read CV NEREA CASAL GARCÍAECSS Paris 2023: OP-AP37
INTRODUCTION: Low-load resistance training (RT) combined with blood flow restriction (BFR) has been shown to promote increases in muscle mass and strength that are typically associated with higher training intensities. However, evidence in female populations remain limited. This study investigated the effects of a 10-week upper-body RT program incorporating low-load practical BFR using non-pneumatic cuffs (pBFR; 20-30% 1RM) compared with a conventional moderate-load RT program performed without BFR (noBFR; 60-70% 1RM). METHODS: Thirty-six healthy, trained women were randomly assigned to either a pBFR group (n = 18; age = 30.3 ± 9.6 years) or a noBFR group (n = 18; age = 31.1 ± 8.3 years). Participants trained three times per week (two upper-body and one lower-body session). Lower-body RT was identical between groups and was not part of the primary research question. Upper-body RT consisted of the bench press, seated row, lat pulldown, shoulder press, all performed at 60–70% of 1RM in both groups. In addition, triceps pushdowns and preacher curls were performed at 20–30% of 1RM using non-pneumatic cuffs in the pBFR group, whereas the noBFR group performed these same exercises without BFR at 60–70% of 1RM. Changes in body composition, arm circumference, muscle thickness, and maximal strength were analyzed using separate two-way mixed factorial ANOVAs with Condition (pBFR vs. noBFR) and Time (Pretest vs. Posttest) as factors. RESULTS: Significant Condition × Time interactions were observed for biceps brachii muscle thickness (p = 0.009; η_p^2 = 0.186) and biceps flexion maximal strength (p = 0.009; η_p^2 = 0.183). Follow-up analyses revealed no between-group differences at each level of Time (p = 0.206–0.705, g = 0.080–0.280 and p=0.544–0.930, g=0.020–0.160, respectively), while both groups demonstrated similar improvements across Time (p < 0.001, g = 1.47–1.96 and p < 0.001, g = 1.42–2.02, respectively). Main effects of time were also observed for muscle mass (p = 0.034, g = 0.37), arm circumferences (p < 0.001, g = 1.49–1.92), triceps brachii muscle thickness (p < 0.001, g =0.81), and maximal strength in the bench press (p < 0.001, g = 1.25), seated row (p < 0.001, g = 1.71), and triceps extension (p < 0.001; g = 1.46). CONCLUSION: In summary, performing low-load pBFR on two upper-body exercises in addition to a standard moderate-load RT program produced gains in muscle size and strength comparable to a conventional moderate-load RT program, in which all exercises were performed at moderate load. Importantly, pBFR was implemented using non-pneumatic cuffs, reflecting real-world training environments where individualized occlusion pressures are limited. These findings suggest that pBFR may effectively compensate for reductions in exercise intensity and represent a viable alternative for women seeking strength and hypertrophy adaptations when higher loads are impractical or undesirable.
Read CV Simon GavandaECSS Paris 2023: OP-AP37
INTRODUCTION: Heavy-load and power resistance training are widely used to develop strength and power in team sports. Whether these modalities induce distinct in-season physiological adaptations remains unclear, and understanding the role of key cellular regulators of adaptation is crucial, yet direct comparative data are scarce. This study compared the effects of heavy-load and power training on muscle fiber adaptations, performance outcomes, and acute cellular responses in handball players. METHODS: Thirty-one resistance-trained female handball players (tier 2) were randomized to HEAVY (n=16; 20±3 yrs) or POWER (n=15; 21±3 yrs). HEAVY performed high-load resistance training (10 sets/week), whereas POWER performed explosive jump exercises (200 jumps/week). Two weekly sessions were conducted during 12 weeks of the competitive season. In the final session (6 heavy sets vs 80 jumps), acute signaling and neuromuscular fatigue were measured. Vastus lateralis biopsies were obtained pre- and post-intervention and 1.5h post-acute session. Outcomes included fiber type distribution, cross-sectional area (CSA), myonuclei, satellite cells, squat 1RM, leg-press power, countermovement jump (CMJ) height, plantar flexor power and stiffness. Acute outcomes included quadriceps isometric force, cellular stress as αB-crystallin immunostaining intensity and protein content in cytosolic and cytoskeletal fractions, and signaling as p-p70S6K and p-ERK1/2. Data were analyzed using two-way repeated-measures ANOVA, with between-group effect sizes (ES). RESULTS: Training attendance was 90% in both groups. Type IIX/IIA fiber proportions decreased by 7 percentage-points in both groups (time p<0.01). Fiber CSA increased more in HEAVY than POWER (IIA: 19% vs -4%, p=0.03; IIX/IIA: 28% vs 3%, p=0.04). Squat 1RM increased more in HEAVY than POWER (15% vs 6%, p<0.01). Leg-press power (10% vs 9%) and CMJ height (6% vs 8%) improved for HEAVY and POWER over time (p<0.01), with no interactions (p>0.41), whereas plantar power and stiffness metrics favored POWER (ES: -0.5 to -0.3). Acute force loss was 10% in HEAVY and 6% in POWER (time p=0.04, no interaction p=0.66, ES=0.2). αB-crystallin in type I fibers was unchanged but increased in type II fibers (time p<0.01; 48% vs 39%, no interaction p=0.51, ES=0.4). αB-crystallin translocation to the cytoskeletal fraction increased more in HEAVY than POWER (p=0.04, ES=0.7). Phosphorylation increased for p70S6K (7-fold vs 4-fold; ES=1.1) and ERK1/2 (2-fold vs 4-fold; ES=–0.6) for HEAVY and POWER respectively (time p<0.01, no interactions (p>0.36). CONCLUSION: During the competitive season, HEAVY training elicited greater type II fiber hypertrophy and strength, while both HEAVY and POWER improved power performance. Acutely, both sessions induced fatigue and cellular stress, with indications of greater response following HEAVY. Effect sizes for p-p70S6K favored HEAVY, consistent with greater hypertrophy, whereas p-ERK1/2 favored POWER, suggesting possible modality-specific signaling responses.
Read CV Fredrik Tonstad VårvikECSS Paris 2023: OP-AP37