Hugo Silva

Silva, H, Morral-Yepes, M, and Abade, E. Reaction time and movement time within the agility time: tools to identify specific goals. J Strength Cond Res 40(6): 709–722, 2026—Agility is a critical component in team sports, encompassing rapid whole-body movements in response to stimuli and can be conceptualized as comprising 2 distinct segments: reaction time, which is the interval between the presentation of a stimulus and the initiation of movement in response to the stimulus; and movement time, which refers to the period between the start and end of the movement corresponding to the reaction. This narrative review presents a conceptual framework on the intricate relationship between these phases, which together shape the expression of agility in athletes. A structured literature search using Boolean operators was conducted across multiple databases, supplemented by backward citation tracking, to identify relevant studies on reaction time and movement time within agility in sports contexts. The review underscores the complexity of reaction time, influenced by the type of stimulus and the athlete's anticipatory skills, and the importance of movement time, affected by multiple factors including rate of force development, neuromuscular coordination, movement amplitude, and task-specific biomechanical demands. Assessment methods for reaction and movement times vary, ranging from general to sport-specific tests. Training interventions targeting these components show promise, with specific protocols improving reaction and movement times, although more research is needed to optimize these strategies, especially regarding movement time. By segmenting agility into reaction and movement times, practitioners can better identify and address athletes' specific needs, leading to more effective training programs. Through clear definitions and a conceptual framework, this review advances understanding of agility and informs practical approaches to training and assessment.

This study aimed to describe and compare warm-up (WU) demands of different protocols (with ball, without ball and pre-match) on female football players. Twenty-two players belonging to the same team were monitored throughout 12 training weeks using global navigation satellite system technology sampling at 10 Hz. The variables used were duration, total distance, distances covered within 0–45%, 45–60%, 60–85%, and 85–100% of individual maximum speed, maximum speed, maximum acceleration, maximum deceleration, number of accelerations of magnitudes between 1 and 2 m/s², 2 and 3 m/s², 3 and 4 m/s², and above 4 m/s², number of decelerations of magnitudes between −1 and −2 m/s², −2 and −3 m/s², −3 and −4 m/s², and below −4 m/s², Player Load, and TRIMP Edwards. A linear mixed model was carried out for each variable in order to analyze the differences between WU protocols. The main results were that pre-match WU showed higher values in the following variables: (1) duration; (2) distances covered within 60–85% and 85–100% of individual maximum speed; (3) maximum speed, acceleration and deceleration; (4) number of accelerations of magnitudes between 2 and 3 m/s² and between 3 and 4 m/s², and more decelerations of magnitudes between −2 and −3 m/s², −3 and −4 m/s² and below −4 m/s²; and, (5) TRIMP Edwards. These findings underscore the importance of WU design in preparing female football players for high-intensity match demands and contribute to the development of specific WU strategies for them.

Silva, H, Monteiro, J, Baptista, J, and Beato, M. Unraveling the physical demands of rondo drills: How different formats shape acceleration and deceleration profiles. J Strength Cond Res 40(5): e454–e459, 2026—Accelerations and decelerations are a critical component in the assessment of training demands in soccer. The characteristics of accelerations (>3 m·s ⁻² ) and decelerations (<–3 m·s ⁻² ) were compared across 3 structured rondo drills (4 vs. 1, 4 vs. 2, 5 vs. 2) performed during 8 minutes in different training sessions. Twenty male elite soccer players (age: 27.1 ± 6.1 years; height: 1.78 ± 0.06 m; body mass: 75.8 ± 7.6 kg) participated for a 10-week period using global navigation satellite systems sampling at 10 Hz. All efforts exceeding the acceleration (>3 m·s ⁻² ) and deceleration (<–3 m·s ⁻² ) thresholds were characterized by duration, magnitude, starting and ending speed, and distance covered. Linear mixed models with post hoc comparisons were used to identify differences between drills. Results showed that the frequency of actions increased with the number of players and pitch size. During the 4 vs. 1 format, players attained greater acceleration magnitudes and higher end speeds than the 4 vs. 2 ( p < 0.001) and 5 vs. 2 formats ( p = 0.003 and p = 0.009, respectively). They also accelerated for longer times and distances in 4 vs. 1 than in 4 vs. 2 formats ( p < 0.01). Conversely, fewer differences were reported in decelerations, with 4 vs. 1 format registering higher magnitudes than the other formats ( p < 0.01) and starting from higher speeds than the 4 vs. 2 format ( p = 0.010). During all formats, players started accelerations and ended decelerations from similar, near-stationary speeds (−1 , p < 0.05). These findings highlight that different rondo formats elicit distinct demands, particularly for accelerations. Therefore, rondos should be carefully planned according to session objectives, because their high intensity may contribute to fatigue and muscle damage, reinforcing the need for careful monitoring and integration within training.

Monitoring high-speed displacements in team sports commonly relies on maximal values, often referred to as Peak Match Speed (PMS). These values are widely used to guide training prescription, injury-prevention strategies, and performance profiling. However, PMS metrics may be distorted by anomalous events, such as tackles or collisions, which generate implausible speed–time patterns and compromise the accuracy of player monitoring. The purpose of this commentary is to present a practical strategy to identify and resolve such abnormalities, thereby increasing the reliability of athlete-monitoring processes. Systematically plotting acceleration-time and speed-time curves together, with the acceleration axis aligned to PMS, allows practitioners to rapidly detect unrealistic patterns, such as extreme accelerations or decelerations near maximal speeds, that deviate from physiological expectations. By identifying and excluding these artefacts, practitioners ensure that derived metrics more accurately reflect players' true physical capacities. This proposed strategy is adaptable to a wide range of team sports and can also enhance the interpretation of submaximal sprint efforts. Importantly, this low-cost and widely applicable approach strengthens the reliability of athlete-tracking outputs, safeguarding both performance analysis and training decision-making.

Purpose : This study characterized change-of-direction (COD) actions in professional soccer players using global navigation satellite systems data, with specific emphasis on COD angle and the associated deceleration (DEC) and re-acceleration (re-ACC) kinematics under match-play conditions. Methods : Data were collected from 52 professional soccer players (mean [SD]: age: 27.3 [5.2] y; body mass: 72.3 [6.9] kg; height: 178.6 [6.8] cm) across 14 official matches, resulting in 3048 individual COD events for analysis. Events were classified by COD angle (15° bins), and DEC and re-ACC phases were detected to extract kinematic variables. Associations between COD angle and selected variables were examined using contingency analyses, and linear mixed-effects models assessed the effects of angle and playing position. Results : CODs, on average, initiated from moderate entry speeds (14.9 km·h ⁻¹ ) and involved substantial braking demands (−4.2 m·s ⁻² ), followed by a short DEC–ACC interval (0.6 s) and a relatively low re-ACC magnitude (1.7 m·s ⁻² ). Contingency analyses revealed a significant association between COD angle and DEC entry speed ( P = .026), with sharper angles showing a slightly greater proportion of moderate-to-high entry speeds. Mixed-effects identified a significant main effect of playing position on DEC entry speed ( P = .035), with higher entry speeds for wide midfielders and forwards compared with central defenders. Conclusions : During soccer matches, CODs have intense braking and rapid DEC–re-ACC coupling despite predominantly submaximal entry and exit speeds. The results support the need for higher DEC thresholds, reflecting match play demands. Additionally, training strategies should account for both angle and entry-speed demands, while considering the playing position.

Purpose : This study compared the temporal structure of high-speed running (HSR) efforts and subsequent recovery profiles between starters and substitutes, and across playing positions, in professional soccer. Methods : Sixty-one male professional players (26.9 [5.2] y) from 2 teams were monitored across 24 official matches, resulting in 215 match observations (148 starters and 67 substitutes). Match running performance was monitored using 10-Hz global navigation satellite system units. Episode-level variables included HSR duration, recovery duration, HSR–recovery intervals, and intervals between consecutive HSR efforts. Linear mixed-effects models were used to compare playing roles, while recovery durations were categorized into 120 s bands and analyzed using χ ² tests. Results : Mean HSR duration did not differ between starters and substitutes (2.37 [1.64] vs 2.40 [1.75] s), nor were differences for HSR–recovery intervals (3.86 [3.59] vs 3.75 [3.55] s), HSR–HSR intervals (3.51 [3.48] vs 3.57 [3.16] s), or the HSR/recovery ratio (1.05 [1.53] vs 1.00 [1.66]) (all P > .05). However, starters displayed significantly shorter recovery durations than substitutes (13.34 [33.51] vs 16.72 [39.50] s; P = .017). Recovery-band distributions differed by playing role ( P < .001), with starters completing a greater proportion (97% vs 93%) of short recoveries ( Conclusions : Despite longer recovery durations in substitutes, the overall temporal structure of HSR efforts was largely consistent between playing roles, with HSR and recovery periods predominantly occurring within short-time windows.

This study compared match peak speeds (MPS) across a full season, considering different playing positions, competitions, match outcomes, and match locations. Thirty-one elite male soccer players were monitored during matches using global navigation satellite system devices. Independent mean differences [95% confidence intervals] were calculated for the investigated variable (MPS). Fullbacks reached higher MPS than central defenders (CD) (d=0.78 [0.56, 1.00]), central midfielders (CM) (d=-0.75 [-0.93, -0.57]) and forwards (d=-0.32 [-0.55, -0.08]); wide midfielders reached higher MPS than CD (d=0.66 [0.43, 0.90]) and CM (d=0.64 [0.45, 0.84]); and forwards reached higher MPS than CD (d=0.46 [0.22, 0.71]) and CM (d=0.41 [0.21, 0.62]). Higher MPS were reached during the National League than the National Cup (d=-0.38 [-0.58, -0.19]) and the Supercup (d=-0.57 [-1.09, -0.06]); higher MPS were reached during the State Cup than the National Cup (d=-0.32 [-0.55, -0.09]) and the Supercup (d=-0.57 [-1.12, -0.05]); and higher MPS were reached during the International Cup than the National Cup (d=0.26 [0.04, 0.48]). Higher MPS were reached during matches lost than won (d=0.19 [0.03, 0.35]). Playing position was the highest differentiator of MPS across a soccer season, underlining the importance of players’ individualization when assessing MPS or when calculating normalized speed thresholds. MPS can also vary between competitions, especially if teams face lower division teams.

The ergogenic effects of caffeine have been reported in scientific literature over a wide spectrum of sporting activities. The current recommendation for caffeine supplementation is ingesting ~ 3–6 mg/kg about 1 h before the onset of exercise. However, some studies reporting caffeine-induced ergogenic effects during exercise have also reported increased activation and reduced sleep quality in the hours after caffeine ingestion. While most of the research on caffeine supplementation for sporting activities recommends the consumption of this stimulant to enhance performance, research focusing on athletes’ sleep quality advises against this decision, especially before competition in the evening or later. Considering that some athletes often compete in the evening or later, the general recommendation of caffeine supplementation may be modified for these athletes as acute caffeine intake in these conditions may produce undesirable side effects such as insomnia and, potentially, reduced performance in subsequent days. In this review, we examine literature on this topic to help athletes and sports practitioners solve the dilemma between the convenience of using caffeine to enhance sports performance or avoiding caffeine to ensure sleep quality. This review identifies potential solutions for this decision, keeping the focus on athletes’ well-being. Overall, the performance response to caffeine and the effect of this substance on sleep quality can vary interindividually and depend on the conditions of the exercise session (time of onset, duration, etc.). For this reason, nutritional practitioners should assess their athletes individually to resolve the conflict between caffeine ingestion and ensuring sleep quality on an individual basis, using simulated competitions with dual measurement of performance during exercise and unwanted effects in the following hours. In addition, the dose, timing, and source of caffeine supplementation can be individually adjusted to obtain performance benefits while reducing side effects for athletes ingesting caffeine before evening sporting events.

This study compares locomotor activities during matches with different recovery intervals (168 h), considering accumulated travel distances (0, 1–250, 251–1,000,>1,000 km) in the previous 3, 5, and 7 days, and match sequence during congested periods. Locomotor data were collected using a global navigation satellite system and included total distance, distance covered between 14–20, 20–25, 25–30, and>30 km/h, maximal speed, maximal accelerations and decelerations, and the number of accelerations and decelerations between 2 and 3 m/s2. Congested fixtures (168 h), with players covering less total distance (p=0.026) and distance at 14–20 km/h (p=0.027) and performing fewer accelerations (p=0.001) and decelerations (p=0.022) between 2 and 3 m/s2. Additionally, interactions with accumulated kilometers traveled revealed that high accumulated distances in the days leading up to congested fixtures exacerbated reductions in locomotor performance (p<0.05). Analysis of specific cases of consecutive congested fixtures showed a decline in locomotor activities after three matches within<72 hours or four matches within<120 hours. These findings highlight the importance of managing fixture schedules and travel distances to optimize player performance and reduce the risk of injury during congested match periods, with limiting players to short match sequences potentially being beneficial.