Postactivation potentiation enhances swim performance in collegiate swimmers

Effects of different warm-up methods on 50-meter breaststroke swimming performance

Purpose

To examine the effects of different warm-up methods on 50 m breaststroke performance in both breaststroke specialists and individual medley swimmers.

Methods

18 swimmers (breaststroke group: 9, individual medley group: 9) who met the qualification standards for the National Intercollegiate Athletic Games participated in this study. Each participant completed four different warm-up protocols (a conventional 1,400 m warm-up and a 700 m conventional warm-up that integrated tubing-assisted (TA), paddle (PD), or squat (SQ) warm-ups) over four separate days. Following each warm-up protocol, a 50 m breaststroke performance test was conducted with inertial measurement unit (IMU) sensors attached to specific body segments to evaluate and compare stroke performance, stroke length, stroke frequency, and the acceleration of the hands, sacrum, and feet across different warm-up methods.

Results

The breaststroke specialists who performed the TA warm-ups recorded significantly less time than those who performed the conventional 1,400 m warm-ups (35.31 ± 1.66 s vs. 35.67 ± 1.83 s, p = 0.006). There was a trend that individual medley specialists who performed the SQ warm-ups recorded less time than those who performed the PD warm-ups (34.52 ± 1.45 s vs. 34.92 ± 1.46 s, p = 0.043). The stroke length of breaststroke specialists following the TA warm-ups was shorter than that following the PD warm-ups, the SQ warm-ups, and the conventional 1,400 m warm-ups. Breaststroke specialists who engaged in the TA warm-ups had higher stroke frequency than those who engaged in the conventional 1,400 m warm-ups, the SQ warm-ups, and the PD warm-ups. During the TA warm-ups, breaststroke specialists exhibited a shorter stroke length and a higher stroke frequency than individual medley specialists. Acceleration data from the center of mass and limb segments, recorded by IMUs, were insufficient to fully explain the variations in stroke frequency, stroke length, and overall performance caused by the different warm-up protocols.

Conclusion

Breaststroke specialists exhibited significant improvement in their 50 m breaststroke performance after the TA warm-up. By contrast, individual medley specialists benefited more from the SQ warm-up.

The Use of the Self-Selected Rest Interval Method Is as Effective for Optimizing Postactivation Performance Enhancement in Elite Athletes as Employing the Best Fixed Rest Interval

ABSTRACT

Fontanetti, G, Barreto, RV, Junior, RC, Marangoni, V, Denadai, BS, Greco, CC, and Lima, LCR. The use of the self-selected rest interval method is as effective for optimizing postactivation performance enhancement in elite athletes as employing the best fixed rest interval. J Strength Cond Res 39(1): 10-15, 2025-This study investigated whether the adoption of a self-selected recovery interval (SSI) is more effective than the use of a fixed recovery interval (FRI) to elicit postactivation performance enhancement (PAPE). Ten male professional volleyball athletes (20.6 ± 1.5 years; 92.8 ± 4.9 kg; 195 ± 8 cm) participated in 3 experimental sessions, in random order, following familiarization with countermovement jump (CMJ) exercises and determination of the load for 5-repetition maximum (5RM: 146 ± 27 kg) squat exercise. The 3 experimental sessions consisted of (a) control session (CON), with measurement of CMJ height 4 minutes before and 2, 4, 6, 8, and 10 minutes after subjects rested while sitting in a chair without performing any preactivation (PA) protocol; (b) session with FRI, with measurement of CMJ height 2, 4, 6, 8, and 10 minutes after performing a PA exercise consisting of 5 squats with 5RM load; and (c) session with SSI, with evaluation of CMJ height once after performing the PA adopting a SSI based on a readiness scale. No significant differences were found between CMJ height in the CON session. Countermovement jump height was higher (p < 0.05) than the baseline measurement at minutes 4, 6, and 8 post-PA in the FRI session, for the best CMJ performance during the FRI session, and after the PA in the SSI session. No significant differences were found between the heights of the best CMJ in the FRI session (49.2 ± 6.8 cm) and post-PA in the SSI session (49.6 ± 6.6 cm). Therefore, adopting FRI and SSI is equally effective in eliciting PAPE in elite athletes. Despite being as effective as adopting FRI to elicit PAPE, SSI is more intuitive and easily applicable in contexts where PAPE can be implemented.

The relationship between load-velocity profiles and 50 m breaststroke performance in national-level male swimmers

This study investigated the relationships between load-velocity profiling and 50 m breaststroke performance. Twenty-seven male swimmers qualified for the national championship participated and performed a 50 m breaststroke trial with a multicamera system. The total race time (t50 m), forward velocity during surface swimming (v50 m), stroke length, and stroke frequency were obtained from the automatic post-processing of the system. Afterwards, the participants performed semi-tethered swimming with three external loads using a robotic resistance device. The average velocity from three stroke cycles was plotted as a function of the corresponding load. The theoretical maximum velocity (v0) and load (L0), L0 normalized to body mass, steepness of the regression line (slope), and active drag (AD) were calculated. The main findings were moderate to large correlations of two 50 m race variables (t50 m and v50 m) with v0, L0, and AD (t50 m range: r = -.444 to r = -.619, p = .020 to p = .001), (v50 m range: r = .451 to r = .568, p = .018 to p = .002). This shows the importance of applying maximum propulsive force to achieve high swimming performance and that load-velocity profiling is an indicator of 50 m breaststroke performance. Load-velocity measurements over time can also monitor velocity, strength, and drag-minimizing abilities, explaining performance changes and training effects.

The Effect of Post-Activation Potentiation Enhancement Alone or in Combination with Caffeine on Anaerobic Performance in Boxers: A Double-Blind, Randomized Crossover Study

Post-activation performance enhancement (PAPE) is a physiological phenomenon that refers to an acute excitation of the neuromuscular system following intense exercise that ends in enhanced physical performance in a subsequent bout of exercise. The scientific literature has primarily examined the effectiveness of PAPE alone or combined with caffeine (CAF) intake in all-out tests lasting ≤10 s, as the effect of PAPE is transitory. The aim of the present study was to determine the effect of a protocol to induce PAPE alone or in combination with caffeine intake on the 30 s Wingate Anaerobic Test in highly trained boxers. Twenty-five male and highly trained boxers (mean age: 20 ± 1 years) participated in a double-blind, randomized crossover study consisting of three different experimental conditions: (i) control (CON), with no substance intake and no PAPE protocol before the Wingate Anaerobic Test; (ii) PAPE + PLA, involving the intake of a placebo 60 min before and a PAPE protocol comprising a 10 s cycling sprint overloaded with 8.5% of the participants' body weight 10 min before the Wingate Anaerobic Test; and (iii) PAPE + CAF, involving the intake of 3 mg/kg of caffeine 60 min before and the same PAPE protocol used in the (ii) protocol before the Wingate Anaerobic Test. In all conditions, the participants performed the 30 s version of the Wingate Anaerobic Test with a load equivalent to 7.5% of their body weight, while the cycle ergometer setting was replicated. Immediately following the Wingate test, heart rate (HR), the rating of perceived exertion (RPE), and blood lactate concentration (Bla) were measured. In comparison to CON, PAPE + PLA enhanced mean power (p = 0.024; Effect size [ES] = 0.37) and total work (p = 0.022; ES = 0.38) during the Wingate test, accompanied by an increase in post-test blood lactate concentration (p < 0.01; ES = 0.83). In comparison to CON, PAPE + CAF enhanced mean power (p = 0.001; ES = 0.57), peak power (p = 0.013; ES = 0.57), total work (p = 0.001; ES = 0.53), post-test blood lactate concentration (p < 0.001; ES = 1.43) and participants' subjective perception of power (p = 0.041). There were no differences in any variable between PAPE + PLA and PAPE + CAF. In summary, a PAPE protocol that involves a 10 s all-out sprint 10 min before the Wingate Anaerobic Test was effective in enhancing Wingate mean power in highly trained boxers. The addition of 3 mg/kg of caffeine to the PAPE protocol produced an effect on mean power of a higher magnitude than PAPE alone, and it enhanced peak power along with participants' subjective perception of power. From a practical point of view, PAPE before exercise seems to be an effective approach for increasing Wingate performance in highly trained boxers, while the addition of caffeine can increase some benefits, especially peak power.

A warm-up strategy with or without voluntary contraction on athletic performance, lower-leg temperature, and blood lactate concentration

It is unclear whether temperature-related warm-up effects can be accomplished by passive warm-up (e.g., by external heat). Therefore, this study compared the effects of two different warm-up protocols with and without voluntary contraction on subsequent sprinting and jumping performance. Eighteen healthy male collegiate students (23.3 ± 2.4 years, 173.8 ± 7.2 cm, 70.5 ± 9.3 kg) randomly experienced 10 min of active (jogging on a treadmill; belt speed: 9.0 km/h at a 1% incline) and passive warm-up (lying down in the warm-up chamber; inner ambient temperature set at 35°C) protocols, followed by ten sets of intermittent exercises in two separate sessions. Athletic performance, lower-leg muscle temperature, and blood lactate concentration were statistically compared using analysis of variance with Tukey-Kramer post-hoc comparisons. Cohen's d effect sizes (ES) were also calculated. There was no warm-up protocol effect over time on 20 m sprint times (condition × time: F9,323 = 1.26, p = 0.25). Maximal vertical jump heights were different (condition × time: F9,323 = 2.0, p = 0.04) such that subjects who performed the active warm-up protocol jumped higher (51.4 cm) than those who did the passive warm-up (49.2 cm, p = 0.04). There was a warm-up protocol effect over time on lower-leg muscle temperature (condition × time: F12,425 = 13.99, p<0.0001) in that there was a 5.5% and 5.8% increase after active (32.8 to 34.6°C, ES = 2.91) and passive (32.9 to 34.9°C, ES = 3.28) warm-up protocols, respectively. Blood lactate concentration was different (condition × time: F2,85 = 3.61, p = 0.03) since the values at the post-warm-up measurements were different between warm-up conditions (active: 4.1 mmol/L; passive: 1.5 mmol/L, p = 0.004, ES = 1.69). Subsequent sprint and jump performance did not differ between the duration- and muscle temperature-matched active and passive warm-up protocols. Non-thermal effects from the warm-up activity may be minimal for sprinting and jumping performance in recreationally active males.

Load-Velocity Profile and Active Drag in Young Female Swimmers: An Age-Group Comparison

PURPOSE

The present study aimed to establish differences in load-velocity profiling, active drag (AD), and drag coefficient (Cd) between 3 age groups of female swimmers.

METHODS

Thirty-three swimmers (11, 13, or 16 y old) were recruited. The individual load-velocity profile was determined for the 4 competitive swimming strokes. The maximal velocity (V0), maximal load (L0), L0 normalized to the body mass, AD, and Cd were compared between the groups. A 2-way analysis of variance and correlation analysis were conducted.

RESULTS

Compared with their younger counterparts, 16-year-old swimmers generally had larger V0, L0, and AD, which was particularly evident when comparing them with 11-year-old swimmers (P ≤ .052). The exception was breaststroke, where no differences were observed in L0 and AD and Cd was smaller in the 16-year-old group than the 11-year-old group (P = .03). There was a negative correlation between Cd and V0 for all groups in backstroke (P ≤ .038) and for the 11-year-old group and 13-year-old group in breaststroke (P ≤ .022) and front crawl (P ≤ .010). For the 16-year-old group, large correlations with V0 were observed for L0, L0 normalized to the body mass, and AD (P ≤ .010) in breaststroke and for L0 and AD with V0 in front crawl (P ≤ .042). In butterfly, large negative correlations with V0 were observed in the 13-year-old group for all parameters (P ≤ .027).

CONCLUSIONS

Greater propulsive force is likely the factor that differentiates the oldest age group from the younger groups, except for breaststroke, where a lower Cd (implying a better technique) is evident in the oldest group.

Reliability of a semi-tethered front crawl sprint performance test in adolescent swimmers

This study aimed to evaluate the test-retest reliability of a sprint performance test with semi-tethered front crawl swimming to indirectly assess the current potential to perform at maximal anaerobic effort in adolescent swimmers. Eight adolescent swimmers participated in this study (gender: females (n = 4) aged 13.0 ± 0.8 years, body height 1.6 ± 0.0 m, body mass 50.1 ± 4.5 kg; and males (n = 4) aged 13.3 ± 1.3 years, body height 1.7 ± 0.1 m, body mass 59.0 ± 8.2 kg. The testing protocol consisted of two trials of 25 m semi-tethered front crawl swimming with maximal effort and with 1 kg resisted isotonic load. Velocity data were recorded automatically by the 1080 Sprint device for 15 m (between 3 m and 18 m). The Fast Fourier Transform algorithm filtered raw instantaneous swimming velocity data in distance (time) function. A third-degree polynomial was used to extract the individual velocity profile, from which the following variables were chosen for test-retest reliability and the assessment of sprint performance: ttrial15, vmax, vmin, tvto max, tvat max, Dto vmax, Dat vmax, fatigue index. Parameters such as vmax, vmin, and ttrial15 were estimated from swimming velocity profiles and considered as reliable. The CV showed low variance <5%; while ICC2,1 demonstrated respectively good (ICC2,1: 0.88), very good (ICC2,1: 0.95), and excellent (ICC2,1: 0.98) rate of relative reliability; and the Bland-Altman index revealed an acceptable agreement (LoA ≤5%) between two measurements. The sprint performance test based on semi-tethered front crawl swimming confirmed that ttrial15, vmax, and vmin were reliable variables to indirectly indicate a potential to perform the maximal anaerobic effort among adolescent swimmers. The evaluation of the swimming velocity profiles allows coaches to monitor the adaptive changes of performance during the training process.

The metronome-based methodology to monitor the stroke length changes in trained swimmers

The aim of our study was to develop a methodology that uses the metronome to constrain the swimmers' stroke rate with the aim to monitor changes in stroke length (SL) during two different periods of the season. Thirteen young trained swimmers (15.7 ± 1.7 y) performed three 50 m front crawl time trials during pre-season (PRE) and after 2 months, during the in-season period (IN). They were asked: (I) to swim at their maximum intensity (NO-MET condition); (II) to synchronize their stroke with a metronome beat set to their preferred intra-stroke-interval (ISI) (100% condition, corresponding to 48 ± 0.7 cycles/min); (III) to synchronize their stroke with a metronome beat set at 5% higher than their preferred ISI (95% condition, corresponding to 51 ± 0.8 cycles/min). The outcome parameters used to evaluate the performance were ISI, SL and total time of 50 m (TT). In NO-MET condition, results showed that TT in IN improved with respect to PRE, but no changes in ISI and SL. In 100% condition, no differences were obtained between the imposed and the performed ISI, whilst in 95% condition, the performed ISI was lower than the metronome ISI, and lower than that in 100% condition. At last, when using the metronome, SL was higher during IN compared to PRE and SL was lower in the 95% condition compared to the 100% condition. Results indicate that the use of the metronome successfully allowed monitoring changes in SL during different periods of the season. This methodology provides valuable information to coaches and athletes to enhance their performance throughout the season.

Regulatory Light-Chain Phosphorylation During Weightlifting Training: Association With Postactivation Performance Enhancement

ABSTRACT

Chiu, LZF, Fry, AC, Galpin, AJ, Salem, GJ, and Cabarkapa, D. Regulatory light-chain phosphorylation during weightlifting training: association with postactivation performance enhancement. J Strength Cond Res 37(10): e563-e568, 2023-Postactivation performance enhancement has been reported for multijoint resistance exercise, with both neural and intrinsic muscle mechanisms suggested as contributing factors. The purpose of this investigation was to examine whether regulatory light-chain (RLC) phosphorylation in a primary mover is associated with enhanced weightlifting performance. Nine male athletes performed 15 sets of 3 repetitions of a multijoint weightlifting activity (clean pull) at 85% 1 repetition maximum. Measures of performance, peak barbell velocity (PV), and average barbell power (AP) were determined by video analysis. Muscle biopsies were taken within 30-60 seconds of completion of the previous lifting set from the vastus lateralis before (PRE), during (MID), and after (POST) a training session. AP was significantly greater for sets 3, 4, and 5 compared with set 1, with large effect sizes (0.8-1.0). Increases in PV did not reach significance; however, the effect size increase for sets 3 and 4 versus set 1 was moderate (0.4). Relative change scores for AP and RLC phosphorylation were positively and negatively correlated at MID (r = 0.60; p = 0.05) and POST (r = -0.74; p = 0.01) exercise, respectively. These data suggest that RLC phosphorylation initially may be associated with postactivation performance enhancement during repeated multijoint exercise.

Acute effects of prior conditioning activity on change of direction performance. A systematic review and meta-analysis

We performed a systematic review and meta-analysis on the acute effects of prior conditioning activity (CA) on change of direction (COD) performance. Eligible studies, involving healthy participants undergoing acute CA with at least one measure of COD performance, were analysed across diverse databases. A total of 34 studies were included for systematic review with 19 studies included for the meta-analysis. The intervention condition resulted in significantly faster (Z = 4.39; standard mean difference [SMD] = 0.49; p < 0.05) COD performance compared with the control condition. Both unloaded and light loaded CA resulted in significantly greater (SMD = 0.58-0.59) COD performance compared to the control condition. Moreover, heavy loaded CA demonstrated a significant but small (SMD = 0.24) improvement in COD performance compared to the control condition. Age and study design had no effect on the overall meta-analysis outcomes. Both males and females exhibited similar moderate effects with CA but only males demonstrated significantly greater COD performance compared to control conditions. Our findings indicate that a range of CA protocols can acutely improve COD performance with unloaded and light-loaded CA resulting in the greatest performance enhancements. These findings will assist practitioners with the design and implementation of appropriate acute CA to improve COD performance.

The Effect of Post-Activation Potentiation on Swimming Starts in Adolescent Swimmers

BACKGROUND

Post-activation potentiation (PAP) is a phenomenon in which there is an increase in induced momentum in sporting activities after muscle contractions. In swimming, the start of the race and the increase in speed in its first few meters are important. The aim of the present study was to investigate the effect of the PAP protocol, which included a simulated body weight start on the ground, on the swimming start and on the 25 m freestyle performance.

METHODS

The study included 14 male and 14 female swimmers, 14.9 ± 0.6 years old. All the swimmers performed three maximal attempts of 25 m freestyle swimming from the starting block on three different days in a randomly counterbalanced order. In each session, swimmers performed either a 25 m freestyle without any intervention before the swimming trial (CG), or performed four vertical simulated ground starts at maximal effort, 15 s before (15 sG) or 8 min before (8 minG) the swimming trial. The jump height, entry distance, flight time, and flight speed for each attempt were calculated.

RESULTS

The CG entry distance was significantly longer than that of the 15 sG and 8 minG (3.39 ± 0.20 vs. 3.31 ± 0.21 and 3.25 ± 0.25 m, respectively, p < 0.001).

CONCLUSIONS

Four simulated swim starts on the ground, 15 s or 8 min before the swim sprint, had no positive effect on the swim start or swim performance, and it is up to the swimmer to perform these jumps.

Swimming Warm-Up and Beyond: Dryland Protocols and Their Related Mechanisms—A Scoping Review

In swimming, the beneficial effects of the in-water warm-up are often undermined by the long transition periods before competition (≥ 20 min). For that reason, studies comparing the effects of in-water warm-ups followed by dryland activities have been conducted in the swimming literature. This has brought conflicting evidence due to large combinations of supervised and unsupervised warm-up procedures used. Therefore, a scoping review was performed to discuss (1) why warm-up strategies are important for competitive swimming; to identify (2) what are the different warm-up approaches available in the literature, and; to establish (3) what are the main conclusions, considerations and gaps that should be addressed in further research to provide clearer guidance for interventions. The search was conducted on PubMed, Web of Science, Scopus, and SPORTDiscus databases. To be considered eligible, studies must have assessed acute short-term responses of warm-up procedures in swimmers by using randomized controlled trials or pre-post study designs. A total of 42 articles were included in this review. The effectiveness of warm-up responses was evaluated based on the inclusion or not of warm-up, the type of conditioning activity (in-water exercise, in-water exercise combined with dryland or dryland exercise only), its duration, and intensity. (1) Warm-up mechanisms have been mainly related to temperature changes associated to cardiovascular adaptations and short-term specific neuromuscular adaptations. Thus, maintaining muscle activity and body temperature during the transition phase immediately prior to competition could help swimmers' performance; (2) the most common approach before a race usually included a moderate mileage of in-water warm-up (~ 1000 m) performed at an intensity of ≤ 60% of the maximal oxygen consumption, followed by dryland protocols to keep the muscle activity and body temperature raised during the transition phase. Dryland activities could only optimize performance in sprint swimming if performed after the in-water warm-up, especially if heated clothing elements are worn. Using tethered swimming and hand-paddles during warm-ups does not provide superior muscular responses to those achieved by traditional in-water warm-ups, possibly because of acute alterations in swimming technique. In contrast, semi-tethered resisted swimming may be considered as an appropriate stimulus to generate post-activation performance enhancements; (3) nothing has yet been investigated in backstroke, butterfly or individual medley, and there is a paucity of research on the effects of experimental warm-ups over distances greater than 100 m. Women are very under-represented in warm-up research, which prevents conclusions about possible sex-regulated effects on specific responses to the warm-up procedures.

The effects of post-activation performance enhancement and different warm-up protocols on swim start performance

This study aimed to examine the effects of post-activation performance enhancement (PAPE) on swim start performance and lower body power performance after different warm-up protocols. Ten male national-level swimmers performed three different warm-ups: (i) a swim-specific warm-up (SW, control protocol); (ii) PAPE (an experimental protocol); and (iii) SW followed by PAPE (SW + PAPE, an experimental protocol). PAPE consisted of performing three series of 5 drop jumps. A repeated-measures ANOVA showed significant differences between the protocols in the swim start performance (F = 8.89; P < 0.001) and countermovement jump (F = 2.22; P = 0.047). SW + PAPE induced greater improvements in swim start time to 15 m (ES = − 0.47, P = 0.017) and entry time (ES = − 1.83, P < 0.001), the countermovement jump reactive strength index modified (ES = − 1.83, P < 0.001), eccentric rate of force development (ES = 0.69, P = 0.047), and index of explosive strength (ES = 0.94, P = 0.005) compared to SW. The current findings of this study indicate that the drop jump PAPE protocol, in addition to SW, is an effective tool because it could improve athletes' capacity for a more efficient swim start and their countermovement jump performance. Furthermore, the results of this study indicate that PAPE induced by drop jumps could be time-efficient and practically applicable in facilities with limited resources.

Upper-Body Post-activation Performance Enhancement for Athletic Performance: A Systematic Review with Meta-analysis and Recommendations for Future Research

BACKGROUND

Research on post-activation performance enhancement (PAPE) is dominated by lower-body conditioning activities/performance test complexes. Despite the contribution of the upper body to many sporting actions, no review on upper-body PAPE currently exists.

OBJECTIVES

The aim of this systematic review with meta-analysis was to provide a synthesis of the available research on the inclusion of upper-body PAPE conditioning activities to improve athletic performance.

METHODS

A review of the literature was conducted according to the Preferred Reporting Items for Systematic Review and Meta-analyses guidelines, including a literature search of EBSCOhost, SPORTDiscus, PubMed and Google Scholar databases. A total of 127 studies were identified through database searches, and were assessed against the following criteria: (1) randomised controlled trial or pre-and-post study design; (2) studies explored the effects of prior voluntary muscle activity, and not electrically induced contractions, (3) evidence, or lack thereof, of PAPE was quantified by the monitoring of individual performance to commonly applied physical tests or sport-specific tasks; (4) conditioning activities and performance tests were primarily upper-body; (5) detailed description of a standardised warm-up; and (6) full-text versions of studies could be accessed in English language peer-reviewed journals. Studies were quality assessed for methodological quality via the PEDro scale and ranked accordingly.

RESULTS

Thirty-one studies met the inclusion criteria. Studies were classified into different conditioning activity modes: bench press variations, sport-specific (modified implement throws, swing-specific, cable pulley, elastic resistance, combination) and bodyweight activity. Acute performance enhancement in several movement-specific combinations was found. A meta-analysis revealed that bench press at  ≥ 80% one repetition maximum significantly (p = 0.03; ES = 0.31) improves subsequent power output in the ballistic bench throw at 30-40% one repetition maximum, following 8-12 min recovery. Additionally, sport-specific overweight implement throws improved subsequent throwing distance at competition weight by ~ 1.7-8.5%; ES = 0.14-0.33, following 3 min recovery. Sport-specific lighter weighted bat swings and swing-specific isometrics resulted in improved subsequent competition weight bat swing velocities, ranging from ~ 1.3-4.9%; ES = 0.16-0.57.

CONCLUSIONS

This review presents several upper-body movement-specific conditioning activities that could be considered by coaches and practitioners as part of complex or contrast training, or used in pre-competition warm-ups to acutely enhance performance.

Proposal of a Conditioning Activity Model on Sprint Swimming Performance

This study aimed to propose a conditioning activity (CA) model to stimulate improvement on neuromuscular responses, mechanical parameters and for the 50-m freestyle swimming. Thirteen male swimmers (19 ± 3 years and performances of 77% in relation to World Championship records) performed four CA protocols followed by a maximum performance in the 50-m freestyle. In the first protocol (P1) swimmers performed a standard warm-up (∼15 min); in the second protocol (P2) lunges (3 × 85% of the one-repetition maximum); in the third (P3) pull-ups (3 maximum repetitions) and box jumps 40 cm high and 60 cm deep (1 × 5 with 10% of the corporal weight); and in the fourth protocol (P4) a combination of exercises from the second and third protocols. CA protocols had no effect on the standard warm-up. However, P2 performance (27.01 ± 1.25 s) was similar to P1 (27.01 ± 1.18 s) and presented higher positive effects in mechanical parameters for the swim start performance in comparison to other protocols, contributing to improvements in the 50-m freestyle. In addition, turnaround time also had a negative effect, mainly in P3 (3.12 ± 0.28 s), signaling the improvement of this variable in all protocols (P1: 3.30 ± 0.38 s; P2: 3.17 ± 0.30 s; P4: 3.17 ± 0.34 s). P2 (after: 80 ± 11%; before: 82.7 ± 9.9%) and P3 (after: 82.7 ± 9.9%; before: 85.1 ± 9.7%) presented a possible positive effect on the percentage of voluntary activation in relation to P1 (after: 79.3 ± 10.7%; before: 76.3 ± 12%). In conclusion, the proposed conditioning activity protocols were not efficient for performance improvement in the 50-m freestyle compared to the standard model and seem to specifically influence each phase of the event.

Effects of 2 Types of Activation Protocols Based on Postactivation Potentiation on 50-m Freestyle Performance

Cuenca-Fernández, F, Ruiz-Teba, A, López-Contreras, G, and Arellano, R. Effects of 2 types of activation protocols based on postactivation potentiation on 50-m freestyle performance. J Strength Cond Res 34(11): 3284-3292, 2020-Postactivation potentiation (PAP) is a phenomenon which improves muscle contractility, strength, and speed in sporting performances through previously applied maximal or submaximal loads on the muscle system. This study aimed to assess the effects of 2 types of activation protocols based on PAP, on sprint swimming performance. A repeated-measures design was used to compare 3 different scenarios before a 50-m race. First, all of the participants performed a standard warm-up (SWU), consisting of a 400-m swim followed by dynamic stretching. This protocol acted as the control. Subsequently, the swimmers were randomly assigned into 2 groups: the swimmers in the first group performed the SWU followed by a PAP one-repetition maximum warm-up (RMWU), consisting of 3 "lunge" and 3 "arm stroke" repetitions, both at 85% of the one-repetition maximum. The swimmers in the second group performed the SWU followed by a PAP eccentric flywheel warm-up (EWU), consisting of one set of 4 repetitions of exercises of both the lower and upper limbs on an adapted eccentric flywheel at the maximal voluntary contraction. The time required for the swimmers to swim 5 and 10 m was shorter with the PAP protocols. The swimming velocity of the swimmers who underwent the EWU and RMWU protocols was faster at 5 and 10 m. The best total swimming time was not influenced by any of the protocols. When isolating swimming (excluding start performance and turn), best time was achieved with the SWU and RMWU compared with EWU (SWU: 20.86 ± 0.95 seconds; EWU: 21.25 ± 1.12 seconds; RMWU: 20.97 ± 1.22 seconds). In conclusion, a warm-up based on PAP protocols might exert an influence on performance in the first meters of a 50-m race. Nevertheless, other factors, such as fatigue, could modify swimming patterns and yield results contradictory to those of the desired task.

Reliability of Load-Velocity Profiling in Front Crawl Swimming

The purposes of this study were to establish test-retest reliability of calculating load-velocity profiles in front crawl swimming using five and three different external loads, and if outcome results were comparable between calculation methods for monitoring performance over time. Fifteen swimmers at either national or international competition level (seven females and eight males) participated in this study. The subjects performed 25 m of semi-tethered swimming with maximal effort with five progressive loads (females 1, 2, 3, 4, and 5 kg and males 1, 3, 5, 7, and 9 kg) as well as 50 m maximal front crawl on 2 different days. The mean velocity during three stroke cycles in mid-pool was calculated and plotted as a function of the external load. Relationship between the load and velocity was expressed by a linear regression line and established for each swimmer. The intercepts between the axes of the plot and the established regression line were defined as theoretical maximum velocity (V₀) and load (L₀). In addition, L₀ was also expressed as a percentage of body mass (rL₀). The coefficient of determination (R²) and the slope (S_lv) of the linear load-velocity relationship were calculated. The intra-class correlation coefficient (ICC) showed excellent agreement (ICC ≥0.902) for all variables. The coefficient of variation was ≤3.14% and typical error was rated as "good" in all variables. A difference was found between day 1 and 2 in V₀ for three- and five-load calculations and for 50 m front crawl time (p < 0.05). No difference was found between the load-velocity profile outcomes variables compared between the three- and five-trial protocols on neither day 1 nor 2. The Bland-Altman plots showed a small bias across all resistance conditions for five loads, L₀: 0.04 kg, rL₀: 0.13%, V₀: -0.03 m/s, and S_lv: 0.003 -m/s/kg and for three loads, L₀: -0.24 kg, rL₀: -0.27%, V₀: -0.04 m/s, S_lv: 0.002 -m/s/kg. In conclusion, the load-velocity profile for front crawl swimming can be calculated with high reliability from both five and three external loads and comparable results in outcome variables were established. These methods can be used to monitor performance parameters over time, and to investigate and compare swimmers' velocity and strength capabilities to allow for individualized training prescription to improve performance.

Post high intensity pull-over semi-tethered swimming potentiation in national competitive swimmers

BACKGROUND

The swimming community has shown considerable interest in using dry-land warm-ups as a method of impacting performance. This study compared the effects of high-resistance pull-over and swimming warm-up in semi-tethered resisted swimming.

METHODS

An incremental-load semi-tethered swimming test was individually administered in 20 national-competitive swimmers to determine the load maximizing swimming power. In different sessions, participants tested such a load 6 min after a swimming warm-up (SWU) or a dry-land warm-up (DLWU: 3 pull-over reps at 85% of the one-repetition maximum). Kinetic variables (velocity, force, acceleration, impulse, power rate of force development [RFD] and intra-cycle variation), were obtained with a linear encoder through trapezoidal integration regarding time. Kinematic variables (distance, time, stroke-rate and stroke-length), were obtained by video recordings. The differences between protocols were observed by paired-samples t-test (ANOVA). Pearson's coefficient explored correlations between kinetics and kinematics variables; significance was set at P<0.05.

RESULTS

DLWU increased RFD (34.52±16.55 vs. 31.29±13.70 N/s; Δ=9.35%) and stroke-rate (64.70±9.84 vs. 61.56±7.07 Hz; Δ=5.10%) compared to SWU, but decreased velocity, force, acceleration, impulse and power. During the incremental-load test velocity and power were higher than obtained after SWU (1.21±0.14 vs. 1.17±0.12 m/s; Δ=3.06%), (51.38±14.93 vs. 49.98±15.40 W; Δ=2.72%), suggesting enhancements prompted by the test itself. Correlations between stroke-length with impulse (r=0.76) and power (r=0.75) associated kinetics with kinematics.

CONCLUSIONS

Potentiation responses were present after the dry-land warm-up. However, swimmers may benefit more from submaximal prolonged conditioning activities such as resisted swimming rather than high-resistance dry-land sets to obtain performance enhancements.

Postactivation potentiation effects of Back Squat and Barbell Hip Thrust exercise on vertical jump and sprinting performance

BACKGROUND

This study aimed to determine and compare the post-activation potentiation (PAP) effects of the Back Squat (SQ-PAP) and Hip Thrust (HT-PAP) exercises in terms of vertical jump height (VJ), 20-yard dash and 40-yard dash time in physically active university students. Considering the Force-vector theory, it was hypothesized that HT-PAP would induce greater potentiation for 40-yard dash than SQ-PAP whereas SQ-PAP would induce greater potentiation for 20-yard dash and VJ than HT-PAP.

METHODS

Seventeen kinesiology and exercise science students (8 male and 9 female) who resistance train at least 3 times/week (age, 21.71±1.49 years; body mass, 75.58±11.89 kg; height, 173.98±11.88 cm and training experience 5.47±2.00 years) joined this study. They performed three experimental sessions namely; baseline (BL), SQ-PAP loading session and HT-PAP loading session with 48 hours interval with a randomized open crossover study design. BL session was also accepted as control and familiarization session. SQ-PAP and HT-PAP exercises were performed roughly at 90% of 1 Repetition maximum (1 RM) of the subjects with three repetitions. Subjects were tested for vertical jump height (VJ), 20-yard dash and 40-yard dash time before and 8 minutes after each PAP loading exercise.

RESULTS

Statistical analysis revealed that the potentiation effects of SQ-PAP and HT-PAP exercises on VJ height, 20-yard and 40-yard dash were similar that none of the loading exercises with 8 min rest interval had any increasing or detrimental performance effect on VJ (P=0.923), 20-yard dash (P=0.133) as well 40-yard dash time (P=0.570).

CONCLUSIONS

These findings demonstrate that none of the loading protocols with above mentioned exercises have any detrimental or improving effects on VJ height, 20-yard dash and 40-yard dash time for physically active university students who joined this study. Although no acute potentiation effect has been found, this study also shows that SQ-PAP, HT-PAP exercises can be used interchangeably and safely to avoid training monotony during longer training periods for chronic adaptations.

Arm-pull thrust in human swimming and the effect of post-activation potentiation

The aim of this study was to analyse the front-crawl arm-pull kinetics and kinematics, comparing it before and after post-activation potentiation (PAP), and the associations between variables describing of the arm-pull kinetics. Twelve male competitive swimmers were randomly assigned to perform two different warm-ups in a crossover manner: (i) non-PAP (control condition); and (ii) PAP (experimental condition). PAP consisted of 2 × 5 arm-pulls with resistance bands by both upper-limbs. Eight minutes later, participants underwent a 25 m all-out trial in front-crawl arm-pull. Kinetics (i.e., peak thrust, mean thrust and thrust-time integral) and kinematics (i.e., speed and speed fluctuation) were collected by an in-house customised system composed of differential pressure sensors, speedo-meter and underwater camera. There was a significant and large improvement of the arm-pull kinetics after completing the warm-up with PAP sets (0.010 < P < 0.054, 0.50 < d < 0.74). There were non-significant and small effects of PAP on speed (P = 0.307, d = 0.18) and speed fluctuation (P = 0.498, d = 0.04). Correlation coefficients among kinetic variables were significant with large associations (0.51 < R < 0.90, 0.001 < P < 0.088). In conclusion, warm-ups including PAP conditioning sets elicit a large improvement in the thrust, but with small improvement in performance. Variables used to characterise thrust are strongly correlated and hence can be used interchangeably.

Human thrust in aquatic environment: The effect of post-activation potentiation on flutter kick

Herein, we analyse by experimental techniques the human kicking thrust and measure the effect of a warm-up routine that includes post-activation potentiation (PAP) sets on front-crawl flutter kick thrust, kinematics, and performance. Sixteen male competitive swimmers with 22.13 ± 3.84 years of age were randomly assigned in a crossover manner to undergo a standard warm-up (non-PAP; control condition) and a warm-up that included PAP sets (PAP; experimental condition) consisting in 2 × 5 repetitions of unloaded countermovement jump. Participants performed a 25 m all-out trial in front-crawl with only flutter kicks eight min after each warm-up. Kinetics (i.e., peak thrust, mean thrust, and thrust-time integral) and kinematics (i.e., speed, speed fluctuation and kicking frequency) were experimentally collected by an in-house customized system composed of differential pressure sensors, speedo-meter, and underwater camera. Peak thrust (P = 0.02, d = 0.66) and mean thrust (P = 0.10, d = 0.40) were increased by 15% in PAP compared to non-PAP. Large and significant differences were noted in speed (P = 0.01, d = 0.54) and speed fluctuation (P = 0.02, d = 0.58), which improved by 10% in PAP compared with non-PAP. In conclusion, a warm-up that includes PAP sets improves kicking thrust, kinematics and performance.

Use of Loaded Conditioning Activities to Potentiate Middle- and Long-Distance Performance: A Narrative Review and Practical Applications

Blagrove, RC, Howatson, G, and Hayes, PR. Use of loaded conditioning activities to potentiate middle- and long-distance performance: a narrative review and practical applications. J Strength Cond Res 33(8): 2288-2297, 2019-The warm-up is an integral component of a middle- and long-distance athlete's preperformance routine. The use of a loaded conditioning activity (LCA), which elicits a postactivation potentiation (PAP) response to acutely enhance explosive power performance, is well researched. A similar approach incorporated into the warm-up of a middle- or long-distance athlete potentially provides a novel strategy to augment performance. Mechanisms that underpin a PAP response, relating to acute adjustments within the neuromuscular system, should theoretically improve middle- and long-distance performance through improvements in submaximal force-generating ability. Attempts to enhance middle- and long-distance-related outcomes using an LCA have been used in several recent studies. Results suggest that benefits to performance may exist in well-trained middle- and long-distance athletes by including high-intensity resistance training (1-5 repetition maximum) or adding load to the sport skill itself during the latter part of warm-ups. Early stages of performance seem to benefit most, and it is likely that recovery (5-10 minutes) also plays an important role after an LCA. Future research should consider how priming activity, designed to enhance the VO2 kinetic response, and an LCA may interact to affect performance, and how different LCAs might benefit various modes and durations of middle- and long-distance exercises.

Post-activation Potentiation Versus Post-activation Performance Enhancement in Humans: Historical Perspective, Underlying Mechanisms, and Current Issues

Post-activation potentiation (PAP) is a well-described phenomenon with a short half-life (~28 s) that enhances muscle force production at submaximal levels of calcium saturation (i.e., submaximal levels of muscle activation). It has been largely explained by an increased myosin light chain phosphorylation occurring in type II muscle fibers, and its effects have been quantified in humans by measuring muscle twitch force responses to a bout of muscular activity. However, enhancements in (sometimes maximal) voluntary force production detected several minutes after high-intensity muscle contractions are also observed, which are also most prominent in muscles with a high proportion of type II fibers. This effect has been considered to reflect PAP. Nonetheless, the time course of myosin light chain phosphorylation (underpinning “classic” PAP) rarely matches that of voluntary force enhancement and, unlike PAP, changes in muscle temperature, muscle/cellular water content, and muscle activation may at least partly underpin voluntary force enhancement; this enhancement has thus recently been called post-activation performance enhancement (PAPE) to distinguish it from “classical” PAP. In fact, since PAPE is often undetectable at time points where PAP is maximal (or substantial), some researchers have questioned whether PAP contributes to PAPE under most conditions in vivo in humans. Equally, minimal evidence has been presented that PAP is of significant practical importance in cases where multiple physiological processes have already been upregulated by a preceding, comprehensive, active muscle warm-up. Given that confusion exists with respect to the mechanisms leading to acute enhancement of both electrically evoked (twitch force; PAP) and voluntary (PAPE) muscle function in humans after acute muscle activity, the first purpose of the present narrative review is to recount the history of PAP/PAPE research to locate definitions and determine whether they are the same phenomena. To further investigate the possibility of these phenomena being distinct as well as to better understand their potential functional benefits, possible mechanisms underpinning their effects will be examined in detail. Finally, research design issues will be addressed which might contribute to confusion relating to PAP/PAPE effects, before the contexts in which these phenomena may (or may not) benefit voluntary muscle function are considered.

Psychophysiological and performance-related responses of a potentiation activity in swimmers of different competitive levels

Athletes' competitive level has an effect on several psychophysiological parameters during the execution of sports-related tasks. This study analyzed the acute effect of a potentiation activity (PAP), composed by 5 loaded box jumps, on specific psychological, physiological and performance-related parameters in 22 trained (COM) and untrained (UNT) adult male swimmers. A control condition was also evaluated. Measurements included the Competitive State Anxiety Inventory, rate of perceived exertion, lower limbs muscle oxygenation, exercise heart rate, vertical jumping ability, 3 different split times and total time-trial performance during an all-out 50-m swim test executed using the breaststroke technique. In addition, total swim strokes and the optimal individual response after the potentiation activity were measured. No significant differences among the two testing conditions were found for all psychological, physiological and performance-related parameters (p > .05) with the exception of total performance time in the UNT group after the PAP condition (41.5 ± 5.3 vs. 41.9 ± 5.5 s; p = .023; ES = 0.6). As expected, the COM group showed enhanced swimming performance during all split times and total time, compared to the UNT group. These results suggest that (i) independently of the training level, psychological responses during sports-related tasks are probably not evident under non-competitive situations and, (ii) competitive level athletes may need more challenging activation stimulus, compared to their less competitive counterparts, to induce the desirable adaptations on the subsequent main activity.

Do Thirty-Second Post-activation Potentiation Exercises Improve the 50-m Freestyle Sprint Performance in Adolescent Swimmers?

Objectives: The purpose of the study was to investigate performance, biomechanical, physiological, and psychophysiological effects of a simple and easily organized post-activation potentiation (PAP) re-warm-up performed before a 50-m freestyle swimming sprint.

Methods: Regional level male adolescent swimmers [age: 13.0 ± 2.0 years; (min 11 years – max 15 years)] performed four trial conditions (three experimental, one control) on different days. The control trial involved a standardized 1200-m warm-up followed by 30 min of rest and a maximal 50-m freestyle swimming sprint. The experimental trials involved the same protocol but added a PAP component after a 20-min rest (10 min pre-50-m): The different PAP component involved the subjects in completing a 30-s maximal effort of: (1) push-ups (PU – upper body), (2) squats (SQ – lower body), and (3) burpees (BP – lower and upper body). Performance (time-trial), biomechanical (stroke length, stroke frequency), physiological (blood lactate concentrations, heart rate), and psychophysiological (ratings of perceived exertion) variables were collected.

Results: The results demonstrated that the PAP protocols used in this investigation had no effect on swimming performance. Before the 50-m swimming sprint, the lactate values were significantly higher after the PU, BP, and SQ PAP loads compared to the control condition [P_(CC-PU) = 0.02; P_(CC-BP) = 0.01; P_(CC-SQ) = 0.04]. For Lactate values, a significant and large effect of experimental condition compared to control condition was found (p < 0.05, η² = 0.68). At 1 min after the 50-m time trial, significant differences were observed between the control condition and the different PAP loads [P_(CC-PU) = 0.01; P_(CC-BP) = 0.04; P_(CC-SQ) = 0.01]. At 3 min after the 50-m sprint, significant differences were found between the control condition and the PU and SQ PAP loads [P_(CC-PU) = 0.018; P_(CC-SQ) = 0.008, respectively]. Additionally, a significant and large effect of experimental condition was found at 1 and 3 min after the 50-m swimming sprint (p < 0.05, η²_{(1 min)} = 0.73; η²_{(3 min)} = 0.59). There were medium sized but non-significant effects of interaction between the conditions, was illustrated for the mean HR values in response to the different conditions (p > 0.05; η² = 0.083).

Conclusion: None of the three PAP protocols showed any significant improvement in performance, biomechanical, physiological, and psychophysiological variables before, during and after the 50-m swimming time-trial. Further studies are warranted to investigate ways to improve swimming performance with simple body mass exercises performed in-between the end of pool warm-up and race start.

Eccentric flywheel post-activation potentiation influences swimming start performance kinetics

This study aimed to assess the effects of post-activation potentiation in the strength related variables of a kick start. Thirteen competitive swimmers performed three kick starts after a standardized warm up (denoted USUAL) and another after inducing post-activation through five isotonic repetitions on an eccentric flywheel (denoted PAP). A T-test was used to quantify differences between USUAL and PAP warm up. The best trial of each subject achieved by natural conditions (denoted PEAK) was compared with data obtained after PAP. An instrumented starting block with independent triaxial force plates, collected the strength variables related with the impulse at take off. Improvements in the vertical components of force were observed after PAP compared with USUAL, meanwhile no differences were detected on the horizontal components of it. The velocity at take off was higher after PAP compared with USUAL (4.32 ± 0.88 vs 3.93 ± 0.60 m*s-1; p = 0.02). No differences in force or velocity were detected comparing PAP with PEAK (4.13 ± 0.62 m*s-1, p = 0.11). The PAP warm-up increased vertical force and it was transferred to a higher resultant velocity at take-off. This improvement would equal the best result possible obtained in natural conditions after some trials.

Effect of Passive, Active and Combined Warm up on Lower Limb Muscle Performance and Dynamic Stability in Recreational Sports Players

INTRODUCTION

Warm up is an activity that is done before a sports activity. The warm up can be done actively and passively. The preferred mode is active warm up in athletes. There are inconclusive effects of passive warm up compared with an active warm up on short term muscle performance. The cumulative effect of passive and active warm up on muscle performance and dynamic stability is not known.

AIM

To find out the effects of passive, active and combined warm up on lower limb muscle performance and dynamic stability in recreational sports players.

MATERIALS AND METHODS

A randomized crossover study was done on 19 recreational lower limb dominant sports players. Three different warm ups were included in the study passive, active and combined. Active warm up included series of activities like cycling, leg press, jump squats, squat jumps while passive warm up included application of moist heat for a period of 20 minutes on lower limb muscles. Combined warm up included both passive and active warm up. Six different sequences were made from these three warm ups. Subjects were screened and allotted into different groups based on the six warm up sequences after sequence randomization with 48 hours wash out period. After every warm up session Vertical Jump Test (VJT) and Star Excursion Balance Test (SEBT) was performed and results were recorded. Study duration was one year and six months.

RESULTS

There was no difference noticed in both the outcome measures. Mean and SD values for passive, active and combined warm up are 47.62±9.64, 48.50±10.16 and 48.87±10.70 respectively in Vertical Jump Test (VJT) and 85.43±8.61, 85.17±8.60 and 85.17±8.38 respectively for SEBT. The p-value for mean difference between passive-active, active-combined, combined-passive are 0.67, 1.00, 0.51 respectively, for VJT and 1.00, 1.00, 1.00 respectively for SEBT.

CONCLUSION

All warm ups are equally effective in short term sports performance.