Juan García-López

While several studies have described the internal load of indoor cycling, only three have assessed pedaling power, all under simulated conditions or with participants aware of the outcomes. The present study analyzed internal and external load during real indoor cycling classes conducted by different instructors. Eleven trained men participated in 130 sessions in which heart rate (HR) and pedaling power were recorded. Results showed high internal load, with mean and peak HR values of ∼81% and ∼94% HRmax, respectively, consistent with intensities classified as “hard” to “very hard.” In contrast, external load was modest, with mean power output of 110–120 W (∼50% maximal aerobic power, MAP) and peak values only slightly exceeding MAP (334 W; <120% MAP). Theoretical power estimated from HR–power regressions (PWC-170 test) was ∼25% higher than the real values obtained. A typical session lasted ∼50 min, with ∼4 min dedicated to warm-up and cool-down and the remainder to the main phase. In conclusion, these findings highlight a systematic decoupling between internal and external load in indoor cycling, underscoring the importance of incorporating structured high-intensity intervals to better align mechanical stimulus with cardiovascular demand.

Footwear may influence postural stability during resistance training, but its effects during bilateral and unilateral squat-based exercises remain poorly understood. This study analyzed the effects of conventional sports footwear on center of pressure (CoP) behavior and vertical ground reaction forces during the barbell back squat and barbell split squat. Eight resistance-trained men completed two sessions. After load determination and familiarization, participants performed both exercises under shod and unshod conditions using a wireless dual force plate system. CoP displacement, CoP velocity, vertical ground reaction forces, and inter-limb vertical force asymmetry were analyzed using a two-way repeated-measures ANOVA. Footwear and exercise type showed moderate or large effects on all analyzed variables, while the footwear × exercise interaction showed moderate or large effects on 12 of 16 variables. CoP displacement and velocity were generally higher under shod than unshod conditions, with moderate to large footwear effects (η²_p = 0.068–0.772). Mediolateral CoP changes were small in the back squat (0.0–6.2%) but clearly larger in the split squat (18.6–28.8%). During the split squat, the dominant/front limb produced greater force unshod than shod, whereas the non-dominant/rear limb showed the opposite pattern. These preliminary findings from this pilot study indicate that conventional sports footwear can alter postural stability and inter-limb vertical force distribution, especially during unilateral squat-based exercises.

Heel elevation is commonly used during the barbell back squat to facilitate ankle dorsiflexion and promote a more upright trunk position. However, its effects on postural stability remain poorly understood, particularly when heel elevation is achieved using wedges rather than specialized footwear. The aim of this exploratory study was to analyze the effects of heel elevation using wedges on postural stability and ground reaction forces during the barbell back squat. Eight healthy young men (22.1 ± 1.7 years; 77.6 ± 7.5 kg; 1.80 ± 0.05 m), all with at least 1 year of resistance training experience, participated in the study. After a familiarization and load-determination session, participants performed 4 sets of 6 repetitions of the barbell back squat at 70% of one-repetition maximum under two conditions: without wedges and with 3 cm heel wedges. Biomechanical data were recorded using a wireless dual force plate system. No significant differences were observed between conditions in mean and peak ground reaction force. In contrast, wedges increased mediolateral center of pressure displacement (+8.8%) and velocity (+7.4%), with the unadjusted analysis showing a significant difference observed for mediolateral displacement. These findings suggest that 3 cm heel wedges do not enhance force output and may be associated with slight impairments in postural stability during squat execution.

Olympic Cross-Country (XCO) mountain biking has evolved since its 1996 Olympic debut, with races becoming up to 40% shorter and more technically demanding.

Purpose : Current literature characterizes cross-country Olympic mountain bike pacing as a “positive strategy” (fast start followed by decline or stabilization). However, this interpretation may be confounded when a start loop (SL), a structurally distinct initial lap included to facilitate positioning, is analyzed with subsequent laps. This study aimed to (1) quantify the influence of the SL on interlap pacing variability and (2) characterize pacing across performance quartiles. Methods : Lap-by-lap timing data were analyzed for 934 elite finishers (543 men, 391 women) across 10 major 2024 events (World Cups, World Championships, and Olympic Games). Seven events included an SL, while 3 did not. Lap speeds were normalized to each athlete’s mean race speed and analyzed using generalized estimating equations to assess lap effects and lap × performance quartile (first vs fourth) interactions. Interlap variability was quantified using coefficient of variation (CV). Results : When only structurally comparable laps were considered, interlap variability was consistently low. Races without an SL showed low variability (median CV < 1.0%), and similar values were observed when the SL was excluded (median CV 1.1% in men and 1.2% in women). Including the SL increased variability approximately 7-fold (median CV 8.5% men and 10.9% women; P < .05). Lap × performance quartile interactions were event-dependent and small. Lower-performing finishers tended to start relatively faster and finish relatively slower than top performers. Conclusions : Excluding the SL reveals relatively stable interlap pacing in elite cross-country Olympic mountain biking with limited between-lap variations, whereas its inclusion substantially inflates variability and accentuates apparent fast-start behavior.

Football is a low-scoring sport where a single goal can determine a team’s success. Understanding shot effectiveness and goalkeeper performance is crucial for optimizing match success. This study aimed to evaluate the effectiveness of shots and goalkeeper interventions by identifying the most favorable areas on the field and within the goal. An observational notational analysis was conducted on 15,266 on-target shots from five major European leagues (Premier League, LaLiga, Bundesliga, Serie A, Ligue 1) during the 2022/2023 season. Data were extracted from FotMob and analyzed in SPSS using Pearson’s chi-square test (χ²) and adjusted residuals (AR) to determine significant patterns. Field and goal zones were divided based on previous studies, with the penalty area receiving further subdivisions due to its relevance to the analysis. The results indicated that match context, target areas within the goal, field zones, and previously identified high-effectiveness areas significantly influenced shot success (χ² < 0.001). Similarly, a significant association was found between the shooting foot and the side of attack (χ² < 0.001), while the body part used did not significantly affect the outcome (χ² = 0.077). Understanding these patterns helps coaches and players optimize team performance. Future studies should analyze additional seasons to confirm these results.

The use of inertial motor units (IMUs) to monitor external training loads during training and competition has grown, particularly in racket sports like badminton. Previous studies highlighted the influence of sensor location on external load measurements, with the lumbosacral region identified as optimal. However, IMUs are often placed dorsally between the scapulae. This study examined the impact of IMU placement (lumbosacral vs. thoracic) on external load recordings during two simulated badminton matches. Sixteen junior international-level players (10 males, 6 females) participated in matches designed to replicate worst-case scenarios (2 × 35 min, 15 min rest). IMUs located on the lumbosacral joint (L) and thoracic area (T) recorded data combining Ultra-Wideband and acceleration technologies. The results showed higher total and sprint distances in T than L (1.0–3.6%, pη² = 0.089–0.182). Small differences were noted for accelerations and decelerations (1.5%, pη² = 0.057) with no significant differences in speed. Conversely, L showed higher values for total impacts and player load (34.6–49.8%, pη² = 0.861–0.868). The findings reveal slight discrepancies in distance and speed based on placement but significant differences in impacts and player loads, warranting further investigation.

This study evaluated the concurrent validity of the Vitruve linear encoder compared to the T-Force device for measuring mean propulsive velocity (MPV) and peak velocity (PV) during the free-weight bench press exercise. Thirteen resistance-trained men participated in three sessions, during which MPV and PV were recorded simultaneously by both devices. The data were analysed using one-way ANOVA, Pearson’s correlation, Bland–Altman analysis, and effect size calculations, with statistical significance set at p ≤ 0.05. The results showed discrepancies between the Vitruve and T-Force devices across different intensity levels. Specifically, the Vitruve device generally reported higher MPV and lower PV values, particularly at moderate and low intensities. Vitruve was deemed useful for MPV measurements, especially at velocities below 0.65 m/s during free-weight bench press exercises. In conclusion, the Vitruve device overestimated MPV and underestimated PV at moderate and low loads (>0.65 m·s⁻¹), with the discrepancies increasing as velocity rose. It can provide valuable data for monitoring and assessing resistance training programs focused on MPV at heavier loads (−1). Researchers and practitioners should take these findings into account when incorporating the Vitruve into velocity-based strength training protocols.

In recent years, advanced footwear technology (AFT) has been shown to improve performance in long-distance road running by altering biomechanics and perceived comfort. This type of footwear is now being marketed for mountain running, although its effects in such races remain unevaluated. This study aimed to examine the impact of AFT on performance, biomechanics, and perceived comfort during a simulated mountain running event. Twelve trained mountain runners participated in a 3-day experiment, with a 7-day recovery between sessions. On the first day, a maximal aerobic speed test assessed the runners’ performance levels. On the second day, participants familiarized themselves with a 5.19 km mountain circuit and comfort scale. On the third day, they completed two time trials on the same circuit, separated by 30 min of passive recovery, using conventional and AFT shoes in a randomized order. Physiological and biomechanical variables were recorded, including body mass, blood lactate, running biomechanics, vertical stiffness, shoe comfort, and rating of perceived exertion (RPE). The findings indicate that AFT does not improve performance or physiological responses during a simulated mountain race, regardless of segment (uphill, downhill, or mixed). However, AFT significantly alters running biomechanics, reducing step frequency and increasing the vertical oscillation of the center of gravity, especially in uphill and downhill sections. While overall comfort remained unchanged, specific differences were observed with AFT. Coaches and practitioners should consider these findings when using AFT in mountain running training or competition.

This study evaluated the concurrent validity of the Vitruve linear encoder compared to the T-Force device for measuring mean propulsive velocity (MPV) and peak velocity (PV) during the free-weight bench exercise. Twelve resistance-trained men participated in three sessions, during which MPV and PV were recorded sim-ultaneously by both devices. The data were analyzed using one-way ANOVA, Pearson's correlation, Bland-Altman analysis, and effect size calculations, with statistical significance set at p ≤ 0.05. The results showed discrepancies between the Vitruve and T-Force devices across different intensity levels. Specifically, the Vitruve device generally reported higher MPV and lower PV values, particularly at moderate and low in-tensities. Vitruve was deemed useful for MPV measurements, especially at velocities below 0.65 m/s during free-weight bench press exercises. In conclusion, the Vitruve device overestimated MPV and underestimated PV at moderate and low loads (> 0.65 m·s⁻¹), with the discrepancies increasing as velocity rose. It can provide valuable data for monitoring and assessing resistance training programs focused on MPV at heavier loads (< 0.65 m·s⁻¹). Researchers and practitioners should take these findings into account when incorporating the Vi-truve into velocity-based strength training protocols.