Post-Activation Potentiation in Strength Training: A Systematic Review of the Scientific Literature

This review aimed to determine the ideal combination of post activation potentiation (PAP) strategies for an improved strength performance. After analysing 202 articles, 15 studies met the inclusion criteria. The findings of this review suggest that a potentiation effect exists as long as a minimum intensity and enough rest are provided. Although intensities of 65% 1RM are sufficient to elicit a potentiation effect, higher effects can be achieved with 85 - 90% 1RM intensities. Similarly, we found that experienced athletes will benefit more from a higher volume bout (1-3 sets), as long as 7-8 minutes of rest are allowed to avoid fatigue

Post-Activation Performance Enhancement as a Strategy to Improve Bench Press Performance to Volitional Failure

Post-Activation Performance Enhancement (PAPE) has been commonly used as a strategy to improve acute force production, although its effects on performance to volitional failure are still unknown. The aim of this study was to analyse the influence of a PAPE protocol on bench press performance in a training set to volitional failure in trained individuals. Fourteen participants with at least two years of resistance training experience (age 24.57 ± 2.7 years; body mass 77.47 ± 12.2 kg; body height 174.21 ± 7.4 cm; medium grip bench press 1 repetition maximum (1RM): 101.6 ± 25.8 kg), of which 14 completed the control protocol and 12 completed the experimental protocol, took part in the study. After a standardised warm-up, participants completed three sessions: 1) a 1RM test for the medium grip bench press, 2) a control condition consisting of a set of the bench press to volitional failure with 80% 1RM (CON), and 3) an experimental condition consisting of a set of the bench press to volitional failure with 80% 1RM after a PAPE protocol (PAPE). The PAPE protocol consisted of a heavy set of one repetition with their 93% 1RM as the conditioning activity. Under the PAPE condition, participants performed significantly more repetitions than under the CON condition (p = 0.008, ES = 0.5, small effect), their last repetition was slower (p = 0.02, ES = 0.52, small effect) and presented a higher velocity loss (p = 0.004, ES = 0.75, moderate effect). These results suggest that a traditional PAPE protocol improves the number of repetitions performed to volitional failure

A Systematic Review of the Effects of Different Resistance Training Volumes on Muscle Hypertrophy

[EN] The main goal of this study was to compare responses to moderate and high training volumes aimed at inducing muscle hypertrophy. A literature search on 3 databases (Pubmed, Scopus and Chocrane Library) was conducted in January 2021. After analyzing 2083 resultant articles, studies were included if they met the following inclusion criteria: a) studies were randomized controlled trials (with the number of sets explicitly reported), b) interventions lasted at least six weeks, c) participants had a minimum of one year of resistance training experience, d) participants' age ranged from 18 to 35 years, e) studies reported direct measurements of muscle thickness and/or the cross-sectional area, and f) studies were published in peer-review journals. Seven studies met the inclusion criteria and were included in the qualitative analysis, whereas just six were included in the quantitative analysis. All participants were divided into three groups: "low" (20 weekly sets). According to the results of this meta-analysis, there were no differences between moderate and high training volume responses for the quadriceps (p = 0.19) and the biceps brachii (p = 0.59). However, it appears that a high training volume is better to induce muscle mass gains in the triceps brachii (p = 0.01). According to the results of this review, a range of 12-20 weekly sets per muscle group may be an optimum standard recommendation for increasing muscle hypertrophy in young, trained men

Influence of Shoe Mass on Performance and Running Economy in Trained Runners

Purpose The aim of this study was to assess the effects of adding shoe mass on running economy (RE), gait characteristics, neuromuscular variables and performance in a group of trained runners. Methods Eleven trained runners (6 men and 5 women) completed four evaluation sessions separated by at least 7 days. The first session consisted of a maximal incremental test where the second ventilatory threshold (VT2) and the speed associated to the VO2max(vVO(2max)) were calculated. In the next sessions, RE at 75, 85, and 95% of the VT(2)and the time to exhaustion (TTE) at vVO(2max)were assessed in three different shoe mass conditions (control, +50 g and +100 g) in a randomized, counterbalanced crossover design. Biomechanical and neuromuscular variables, blood lactate and energy expenditure were measured during the TTE test. Results RE worsened with the increment of shoe mass (Control vs. 100 g) at 85% (7.40%, 4.409 +/- 0.29 and 4.735 +/- 0.27 kJ.kg(-1).km(-1),p= 0.021) and 95% (10.21%, 4.298 +/- 0.24 and 4.737 +/- 0.45 kJ.kg(-1).km(-1),p= 0.005) of VT2. HR significantly increased with the addition of mass (50 g) at 75% of VT2(p= 0.01) and at 75, 85, and 95% of VT2(p= 0.035, 0.03, and 0.03, respectively) with the addition of 100 g. TTE was significantly longer (similar to 22%, similar to 42 s,p= 0.002,ES= 0.149) in the Control condition vs. 100 g condition, but not between Control vs. 50 g (similar to 24 s,p= 0.094,ES= 0.068). Conclusion Overall, our findings suggest that adding 100 g per shoe impairs running economy and performance in trained runners without changes in gait characteristics or neuromuscular variables. These findings further support the use of light footwear to optimize running performance

Influence of advanced shoe technology on the top 100 annual performances in men's marathon from 2015 to 2019.

[EN]The NIKE Vaporfly shoe was introduced in May 2017 as part of the original #Breaking2 Project (an event aimed to run the first marathon under 2h). This new advanced shoe technology (NAST) changed the footwear design conception. The aim of this study was (i) to analyse the effect of NAST in men's marathon performance, (ii) to analyse whether the changes in the environmental constraints (temperature and wind) and orography of the marathons, age and birthplace of the runners has changed from 2015 to 2019 and (iii) to analyse the impact of NAST on the historical 50 best performances. Data from top-100 men's marathon performances were collected in that timeframe. The shoes used by the athletes were identified (in 91.8% of the cases) by publicly available photographs. External and environmental conditions of each marathon and age and birthplace of the runners were also analysed. Marathon performances improved from 2017 onwards between 0.75 and 1.50% compared to 2015 and 2016 (p<0.05). In addition, the improvement was greater in the upper deciles than in the lower ones (p<0.001). Runners wearing NAST ran~1% faster in marathon compared to runners that did not use it (p<0.001). When conducting an individual analysis of athletes who ran with and without NAST, 72.5% of the athletes who completed a marathon wearing NAST improved their performance by 0.68% (p<0.01). External and environmental conditions, age or birthplace of runners seems not to have influenced this performance improvement. NAST has had a clear impact on marathon performance unchanged in the environmental constraints (temperature and wind), orography, age, and birthplace of the runners but with differences between venues.This work was financed by groups grants from the University of Castilla-La Mancha and co-financed by the European Union through the European Regional Development Fund. Research Group: Grupo de Investigación Rendimiento Deportivo (GIRD)

The Effect of Different Cadence on Paddling Gross Efficiency and Economy in Stand-Up Paddle Boarding

Background: Due to the importance of energy efficiency and economy in endurance performance, it is important to know the influence of different paddling cadences on these variables in the stand-up paddleboarding (SUP). The purpose of this study was to determine the effect of paddling at different cadences on the energy efficiency, economy, and physiological variables of international SUP race competitors. Methods: Ten male paddlers (age 28.8 ± 11.0 years; height 175.4 ± 5.1 m; body mass 74.2 ± 9.4 kg) participating in international tests carried out two test sessions. In the first one, an incremental exercise test was conducted to assess maximal oxygen uptake and peak power output (PPO). On the second day, they underwent 3 trials of 8 min each at 75% of PPO reached in the first test session. Three cadences were carried out in different trials randomly assigned between 45–55 and 65 strokes-min−1 (spm). Heart rate (HR), blood lactate, perceived sense of exertion (RPE), gross efficiency, economy, and oxygen uptake (VO2) were measured in the middle (4-min) and the end (8-min) of each trial. Results: Economy (45.3 ± 5.7 KJ·l−1 at 45 spm vs. 38.1 ± 5.3 KJ·l−1 at 65 spm; p = 0.010) and gross efficiency (13.4 ± 2.3% at 45 spm vs. 11.0 ± 1.6% at 65 spm; p = 0.012) was higher during de 45 spm condition than 65 spm in the 8-min. Respiratory exchange ratio (RER) presented a lower value at 4-min than at 8-min in 55 spm (4-min, 0.950 ± 0.065 vs. 8-min, 0.964 ± 0.053) and 65 spm cadences (4-min, 0.951 ± 0.030 vs. 8-min, 0.992 ± 0.047; p < 0.05). VO2, HR, lactate, and RPE were lower (p < 0.05) at 45 spm (VO2, 34.4 ± 6.0 mL·kg−1·min−1; HR, 161.2 ± 16.4 beats·min−1; lactate, 3.5 ± 1.0 mmol·l−1; RPE, 6.0 ± 2.1) than at 55 spm (VO2, 38.6 ± 5.2 mL·kg−1·min−1; HR, 168.1 ± 15.1 beats·min−1; lactate, 4.2 ± 1.2 mmol·l−1; RPE, 6.9 ± 1.4) and 65 spm (VO2, 38.7 ± 5.9 mL·kg−1·min−1; HR, 170.7 ± 13.0 beats·min−1; 5.3 ± 1.8 mmol·l−1; RPE, 7.6 ± 1.4) at 8-min. Moreover, lactate and RPE at 65 spm was greater than 55 spm (p < 0.05) at 8-min. Conclusion: International male SUP paddlers were most efficient and economical when paddling at 45 spm vs. 55 or 65 spm, confirmed by lower RPE values, which may likely translate to faster paddling speed and greater endurance

Influence of the biomechanical variables of the gait cycle in running economy. [Influencia de variables biomecánicas del ciclo de paso en la economía de carrera].

<p algn="justify">The aim of this study was to investigate the relationships between biomechanical variables and running economy (RE). Eleven recreational (RR) and 14 well-trained runners (WT) completed 4 min stages on a treadmill at different speeds. During the test, biomechanical variables such as ground contact time (tc), swing time (tsw), stride length, frequency and angle and the length of the different subphases of ground contact were calculated using an optical measurement system. VO2 was measured in order to calculate RE. The WT runners were more economical than the RR at all speeds and presented lower tc, higher tsw, longer strides, lower stride frequencies and higher stride angles (P<0.05). Similarly, the WT runners experienced a later propulsion subphase than the RR runners (P<0.05). RE was positively related to tc, stride frequency and 10-km race pace, whereas it was negatively related to tsw, stride length, stride angle and the propulsive subphase. Our results suggest that running patterns characterized by longer stride lengths and higher stride angles, lower stride frequencies and tc, higher tsw and later propulsion suphases may enable an efficient energy use per stride. </p> Resumen <p align="justify">El objetivo de este estudio fue el investigar las relaciones entre diferentes variables biomecánicas y la economía de carrera (RE). Once atletas populares (RR) y 14 atletas altamente entrenados (WT) completaron estadios de 4 min en tapiz rodante a diferentes velocidades. Durante el test, el tiempo de contacto (tc) y de vuelo (tsw), la longitud, frecuencia y ángulo de zancada y la duración de las diferentes sub-fases del tiempo de contacto se calcularon usando un sistema óptico. Se midió el VO2 para calcular la RE. Los atletas WT fueron más económicos que los RR y presentaron menores tc, mayores tsw, zancadas más largas, frecuencias más bajas y ángulos mayores (P<0.05). Además, los atletas WT experimentaron la sub-fase propulsiva más tarde que los RR (P<0.05). La RE estuvo positivamente relacionada con el tc, la frecuencia de zancada y el ritmo de 10 km, mientras que estuvo negativamente relacionada con el tsw, longitud y ángulo de zancada y la sub-fase propulsiva. Estos resultados sugieren que una biomecánica caracterizada por zancadas más largas, ángulos de zancada y tsw mayores, menores frecuencias y tc, y sub-fases propulsivas más tardías pueden favorecer un uso energético más eficiente.</p

Regional Hypertrophy: The Effect of Exercises at Long and Short Muscle Lengths in Recreationally Trained Women

The aim of the present study was to analyse the role of exercises' resistance profile in regional hypertrophy. Thirty-eight healthy women completed a 9-week resistance training program consisting of either 4 sets of 12 repetitions to volitional failure of inclined bicep curls (INC group) or preacher curls (PREA group), three times per week. Pre- and post-intervention muscle thickness was measured using B-mode ultrasound imaging with a linear-array transducer. Scan acquisition sites were determined by measuring 50%, 60% and 70% of the distance between the posterior crest of the acromion and the olecranon. Statistical significance was set at p < 0.05. No region of the INC group grew when comparing pre- to post-intervention. The 70% region of the PREA group grew significantly (muscle thickness increased from 2.7 ± 0.43 cm to 2.94 ± 0.44 cm). We found no growth differences between regions when analysing per group (p = 0.274), region (p = 0.571) or group*region (p = 0.367). Our results show that the distal region of the arm grows in response to the preacher curl that places the highest amount of strain in the range of motion in which the arm muscles are more elongated

The International Olympic Committee framework on fairness, inclusion and nondiscrimination on the basis of gender identity and sex variations does not protect fairness for female athletes

The International Olympic Committee (IOC) recently published a framework on fairness, inclusion, and nondiscrimination on the basis of gender identity and sex variations. Although we appreciate the IOC's recognition of the role of sports science and medicine in policy development, we disagree with the assertion that the IOC framework is consistent with existing scientific and medical evidence and question its recommendations for implementation. Testosterone exposure during male development results in physical differences between male and female bodies; this process underpins male athletic advantage in muscle mass, strength and power, and endurance and aerobic capacity. The IOC's “no presumption of advantage” principle disregards this reality. Studies show that transgender women (male-born individuals who identify as women) with suppressed testosterone retain muscle mass, strength, and other physical advantages compared to females; male performance advantage cannot be eliminated with testosterone suppression. The IOC's concept of “meaningful competition” is flawed because fairness of category does not hinge on closely matched performances. The female category ensures fair competition for female athletes by excluding male advantages. Case-by-case testing for transgender women may lead to stigmatization and cannot be robustly managed in practice. We argue that eligibility criteria for female competition must consider male development rather than relying on current testosterone levels. Female athletes should be recognized as the key stakeholders in the consultation and decision-making processes. We urge the IOC to reevaluate the recommendations of their Framework to include a comprehensive understanding of the biological advantages of male development to ensure fairness and safety in female sports