ECSS Paris 2023: CP-AP19
INTRODUCTION: Contrast training (CT) involves resistance exercises of maximal or high intensity before performing a lighter resistance plyometric movement with similar biomechanical properties. The aim of this study was to investigate the effect of different intensities of acute multiset CT on jump performance in trained women METHODS: Fourteen volunteer woman athletes (age= 25.2± 5.2 years) with a regular menstrual cycle (26.1± 1.8 days) and experience in strength and plyometric training (3.79± 1.57 years) were randomised to 2 different intensities (90% 1RM - 65% 1RM) at the same time of day (15:30-17:00 h), with 48 hours interval, during the late follicular phase of their menstrual cycle (days 7-12). CT was performed in three sets, consisting of three repetitions of back squat exercise at the specified intensity, followed by three Counter Movement Jump (CMJ) as an explosive exercise. Participants performed 2 CMJ before CT, and the acute effect of 2 different intensities of CT on jump performance was assessed with CMJ tests repeated at the 1 st and 3 st minutes after 3 sets of CT. Data were analysed using a 2x3 (intensity x time) repeated measures two-way ANOVA RESULTS: ANOVA analysis showed that the effect of intensity (F(1,13) =3.230, p=0.096, η2 =0.199) and the interaction between intensity and time (F(2,12) =1.088, p=0.344, η2 =0.077) were not statistically significant. However, the effect of time on jump performance was statistically significant (F(2,12) =4.638, p=0.024, η2 =0.263). The jump height was lower than the reference value at 1 min after the CT (p=0.027), whereas at 3 rd mins, it was similar with the reference value (p=0.282) CONCLUSION: The study found no significant difference in the jump performance of woman athletes after CT, regardless of the intensity
Read CV Çisil SönmezECSS Paris 2023: CP-AP19
INTRODUCTION: Muscle fatigue and soreness often occur after high-intensity exercise, particularly when eccentric contractions are involved. Women (W) show lower fatigability in low-intensity isometric tasks, but this advantage fades at higher intensities. In dynamic contractions, W fatigue less than men (M), yet may experience greater power loss in high-load eccentric tasks. Pedalling cadence influences muscle fiber recruitment, yet its impact on performance and fatigue across sexes remains unclear. W may exhibit less muscle pain and recover faster due to oestrogen effects. This study examines sex-based differences in muscle strength, pain perception and sprinting capacity across different cadences during recovery before and after a fatiguing protocol with a strong eccentric component (FP). We hypothesise that M will experience greater muscle pain, while W will exhibit a reduced loss in strength and sprint performance. METHODS: Eighteen young active participants (9M/9W) completed a familiarisation and DXA evaluation. Pre-testing included 1RM (bench press (BP) & squat (SQ)), sprint capacity test (SpC) (6x6s sprints, 24s recovery at 80 and 110rpm) and two 30sWingate (WG) with 20s occlusion in between, 5 min between tests. The automated constant leg pressure device (CLPD) and a visual analogue scale assessed pain. The FP included 5 sets of BP (105% 1RM, eccentric-only) & SQ to failure (5 sets: 80-60% 1RM),120 drop jumps, and repeated cycling sprints. Post-testing was performed 24h (pain and strength) and 48h (pain, strength and SpC) after FP. RESULTS: Muscle pain increased at 24-48h post-exercise, more in W than M, particularly in chest and legs (p<.05). In both sexes 1RM-strength declined (SQ: 16.3% at 24h, 12.1% at 48h; BP: 22.7% at 24h, 18.8% at 48h). M had higher baseline PPO and MPO (+11 and 9.8%) in Watts/kg-leg lean mass (W/kg-LLM) during the SpC than W (p<.05). At 48h, PPO (7.2%) and MPO (5.7%) were reduced (p>0.05), regardless of sex. At baseline, PPO during WG1 was higher in men (p=.047), with a performance loss of 42% in WG2 (P<.001). At 48h, PPO in WG1 was decreased by 2.5% in M and 9.4% in W, while in WG2, it increased 9.2% in M and decreased 2.1% in W. This led to a PPO drop only in W (6.7%, Time×Sex interaction P=.072). This trend disappeared when adjusting for baseline fitness (1RM/LLM, PPO/LLM, MPO/LLM) as covariates. Higher pedalling cadence (110rpm) resulted in superior MPO compared to 80rpm (~6.2%, p=.006). CONCLUSION: Both sexes showed significant declines in strength and SpC after a FP, with W reporting greater muscle pain and a larger WG performance loss, likely due to a lower anaerobic capacity per unit of muscle at baseline. Higher cadence allowed for a greater MPO pre- and post- FP. These findings suggest that sex-specific muscle traits influence recovery patterns, warranting further research into underlying physiological mechanisms. PID2021-125354OB-C21/AEI/10.13039/501100011033/FEDER, EU. CSD (EXP_75097). AGS: Catalina Ruiz postdoctoral grant (CUCIC-GOBCAN and ESF)
Read CV Elisabetta De NigrisECSS Paris 2023: CP-AP19
INTRODUCTION: Despite the well-established use of progressive training overload (PTO) and total load (TL), training monitoring and other training principles are often overlooked in animal model research, creating a gap in understanding their potential impact on performance outcomes and translational effects. This study investigates whether greater training loads equate to superior performance while also considering training monitoring metrics such as Training Monotony (TM) and internal TL. METHODS: 70-day-old male Sprague-Dawley rats were assigned to 3 groups: Sedentary (SED, n=10), Continuous Training (CTR, n=13), or Interval Training (ITR, n=9). All animals underwent a 1-week treadmill familiarization. CTR and ITR trained 3x/week for 4 weeks. External TL was set at 34,200 arbitrary units (AU) for CTR and 16,950 AU for ITR. PTO was applied biweekly with a 22% and 18% AU increment for CTR and 15% and 13% AU increment for ITR. Running sessions: CTR—40 min at low-intensity; ITR—18 min (3 cycles of 2-min moderate-intensity + 4-min low-intensity recovery). Performance was assessed post-familiarization (week 0), at week 2, and at week 4, using external work (EW), calculated in Joules [2]. Training monitoring was conducted via lactate-based TRIMP (TRIMPLac) for internal TL at weeks 1 and 3. TM remained constant at 1.24 AU in both training groups [3]. The statistical analysis was performed using a mixed linear model to assess time and group effects on EW and TRIMPLac. The time×group interaction was explored via post hoc comparisons (Bonferroni correction). The effect size was estimated using Cohen’s d. Statistical significance was set at p<0.05. RESULTS: CTR and ITR groups improved EW compared to the baseline and the SED group. A significant main effect of time was observed (B=12.84, 95% CI: 9.21–16.47, p<0.001); indicating an overall enhancement in performance. Post hoc comparisons confirmed significant improvements in performance for CTR (Δ=23.6%, p<0.001) and ITR (Δ=19.8%, p<0.001) from baseline to post-intervention. The effect size for training was large (CTR: d=1.74; ITR: d=1.61), reinforcing the efficacy of the interventions. No significant EW difference was found between CTR and ITR (Δ=3.8%, p=0.289), despite external TL in CTR being more than double that of ITR. While TM remained equivalent across groups, TRIMPLac did not differ between CTR and ITR at week 1; however, at week 3, CTR exhibited significantly higher TRIMPLac than ITR (p<0.001). CONCLUSION: Higher training loads do not necessarily translate into superior performance outcomes. Training adaptations in rodent models are not solely determined by absolute external TL, and might be influenced by additional physiological and methodological factors such as TM and TRIMPLac. These implications highlight the relevance of our research and its potential to shape future studies in the field. References: 1. Robinson et al. (2019); 2. Soares et al. (2019); 3. Foster (1998).
Read CV Arthur SilvaECSS Paris 2023: CP-AP19