Relative pedaling forces are low during cycling.

We quantified and compared the mechanical force demands relative to the maximum dynamic force (MDF) of 11 cyclists when pedaling at different intensities (ventilatory threshold, maximum lactate steady state, respiratory compensation point, and maximal aerobic power), cadences (free, 40, 60 and 80 rpm), and all-out resisted sprints. Relative force demands (expressed as %MDF) progressively increased with higher intensities (p < 0.001) and lower cadences (p < 0.001). Notwithstanding, relative force demands were low (<54 % MDF) for all conditions, even during the so-called 'torque training'. These results might be useful when programming on-bike resistance training to improve torque production capacity.

Effects of multicomponent training and HMB supplementation on disability, cognitive and physical function in institutionalized older adults aged over 70 years: a cluster-randomized controlled trial.

OBJECTIVES: To investigate the synergist effects of exercise and ß-hydroxy ß-methylbutyrate (HMB) supplementation on disability, cognitive and physical function, and muscle power in institutionalized older people. DESIGN: Cluster-randomized controlled trial. PARTICIPANTS: Seventy-two institutionalized older adults (age = 83 ± 10 years old; 63% women) were randomized in four groups: exercise plus placebo (EX), HMB supplementation, EX plus HMB supplementation (EX + HMB), and control (CT). INTERVENTION: The exercising participants completed a 12-week tailored multicomponent exercise intervention (Vivifrail; 5 days/week of an individualized resistance, cardiovascular, balance and flexibility program), whereas the HMB groups received a drink containing 3 g/day of HMB. MEASUREMENTS: Participants were assessed Pre and Post intervention for disability and cognitive function (validated questionnaires), physical function (short physical performance battery, SPPB), handgrip strength and sit-to-stand relative muscle power. Linear mixed-effect models were used to compare changes among groups. RESULTS: Compared to baseline, both EX and EX + HMB improved cognitive function (+2.9 and +1.9 points; p < 0.001), SPPB score (+2.9 points and +2.4 points; p < 0.001) and relative muscle power (+0.64 and +0.48 W·kg-1; p < 0.001), while CT and HMB remained unchanged (p > 0.05). Significant between-group differences were noted between CT, EX and EX + HMB for cognitive function (p < 0.01), between CT and EX + HMB for physical function (p = 0.043), and between CT, EX and EX + HMB for relative muscle power (p < 0.001). CONCLUSION: The Vivifrail exercise program was effective in improving cognitive and physical function, and muscle power in nursing home residents, while HMB supplementation did not provide additional benefits when combined with exercise. These results emphasize the importance of physical exercise interventions in very old people as an essential basis for improving their overall health and quality of life.

Torque-Cadence Profile and Maximal Dynamic Force in Cyclists: A Novel Approach.

We aimed to determine the feasibility, test-retest reliability and long-term stability of a novel method for assessing the force (torque)-velocity (cadence) profile and maximal dynamic force (MDF) during leg-pedaling using a friction-loaded isoinertial cycle ergometer and a high-precision power-meter device. Fifty-two trained male cyclists completed a progressive loading test up to the one-repetition maximum (1RM) on a cycle ergometer. The MDF was defined as the force attained at the cycle performed with the 1RM-load. To examine the test-retest reliability and long-term stability of torque-cadence values, the progressive test was repeated after 72 h and also after 10 weeks of aerobic and strength training. The participants' MDF averaged 13.4 ± 1.3 N·kg-1, which was attained with an average pedal cadence of 21 ± 3 rpm. Participants' highest power output value was attained with a cadence of 110 ± 16 rpm (52 ± 5% MDF). The relationship between the MDF and cadence proved to be very strong (R2 = 0.978) and independent of the cyclists' MDF (p = 0.66). Cadence values derived from this relationship revealed a very high test-retest repeatability (mean SEM = 4 rpm, 3.3%) and long-term stability (SEM = 3 rpm, 2.3%); despite increases in the MDF following the 10-week period. Our findings support the validity, reliability and long-term stability of this method for the assessment of the torque-cadence profile and MDF in cyclists.

Load-velocity Relationship of the Bench Press Exercise is not Affected by Breast Cancer Surgery and Adjuvant Therapy.

We examined the effect of breast cancer surgery and adjuvant therapy on the relationship between bar velocity and relative intensity (load-velocity [L-V] relationship) of the bench press (BP) exercise. Twenty-two breast cancer survivors (age: 48.0±8.2 yr., relative strength: 0.40±0.08) completed a loading test up to the one-repetition maximum (1RM) in the BP using a lightweight carbon bar. General and individual relationships between relative intensity (%1RM) and mean propulsive velocity (MPV) were studied. Furthermore, the mean test velocity (MPVTest) and velocity attained to the 1RM (MPV1RM) were analyzed. These procedures and analyses were also conducted in 22 healthy women (age: 47.8±7.1 yr., relative strength: 0.41±0.09) to examine the differences in velocity parameters derived from these L-V relationships. Polynomial regressions showed very close relationships (R2≥0.965) and reduced estimation errors (≤4.9% 1RM) for both groups. Between-group differences in MPV attained to each %1RM were small (≤0.01 m·s-1) and not significant (p≥0.685). Similarly, the MPVTest (0.59±0.06 m·s-1) and MPV1RM (0.17±0.03 m·s-1) were identical for breast cancer survivors and healthy women. These results suggest that practitioners could use the same velocity parameters derived from the BP L-V relationship to prescribe this exercise in middle-aged women, regardless of whether they have suffered from breast cancer.

Free-Weight and Machine-Based Training Are Equally Effective on Strength and Hypertrophy: Challenging a Traditional Myth.

PURPOSE: This study aimed to compare the effects of free-weight and machine-based resistance training on strength, hypertrophy, and joint discomfort. METHODS: Thirty-eight resistance-trained men participated in an 8-wk resistance program allocated into free-weight ( n = 19) or machine-based ( n = 19) groups. Training variables were identical for both modalities, so they only differed in the use of barbells or machines to execute the full squat, bench press, prone bench pull, and shoulder press exercises. The velocity-based method was implemented to accurately adjust the intensity throughout the program. Strength changes were evaluated using eight velocity-monitored loading tests (four exercises × two modalities) and included the relative one-repetition maximum (1RM Rel ), as well as the mean propulsive velocity against low (MPV Low ) and high (MPV High ) loads. Ultrasound-derived cross-sectional area of quadriceps (proximal and distal regions), pectoralis major, and rectus abdominis was measured to examine hypertrophy. Complementarily, Western Ontario and McMaster Universities and Disabilities of the Arm, Shoulder and Hand questionnaires were administrated to assess changes in lower- and upper-limb joint discomfort. Outcomes were compared using ANCOVA and percentage of change (∆) statistics. RESULTS: Each group significantly ( P < 0.001) increased 1RM Rel , MPV Low , and MPV High for both modalities tested, but especially in the one they trained. When considering together the eight exercises tested, strength changes for both modalities were similar (∆ differences ≤1.8%, P ≥ 0.216). Likewise, the cross-sectional area of all the muscles evaluated was significantly increased by both modalities, with no significant differences between them (∆ difference ≤2.0%, P ≥ 0.208). No between-group differences ( P ≥ 0.144) were found for changes in stiffness, pain, and functional disability levels, which were reduced by both modalities. CONCLUSIONS: Free-weight and machine-based modalities are similarly effective to promote strength and hypertrophy without increasing joint discomfort.

Adaptations in athletic performance and muscle architecture are not meaningfully conditioned by training free-weight versus machine-based exercises: Challenging a traditional assumption using the velocity-based method.

BACKGROUND: Although the superior effectiveness of free-weight over machine-based training has been a traditionally widespread assumption, longitudinal studies comparing these training modalities were scarce and heterogeneous. OBJECTIVE: This research used the velocity-based method to compare the effects of free-weight and machine-based resistance training on athletic performance and muscle architecture. METHODS: Thirty-four resistance-trained men participated in an 8-week resistance training program allocated into free-weight (n = 17) or machine-based (n = 17) groups. Training variables (intensity, intraset fatigue, and recovery) were identical for both groups, so they only differed in the use of a barbell or specific machines to execute the full squat, bench press, prone bench pull, and shoulder press exercises. The velocity-based method was implemented to accurately adjust the planned intensity. Analysis of covariance and effect size (ES) statistics were used to compare both training modalities on a comprehensive set of athletic and muscle architecture parameters. RESULTS: No between-group differences were found for any athletic (p ≥ 0.146) and muscle architecture (p ≥ 0.184) variable. Both training modalities significantly and similarly improved vertical jump (Free-weight: ES ≥ 0.45, p ≤ 0.001; Machine-based: ES ≥ 0.41, p ≤ 0.001) and lower limb anaerobic capacity (Free-weight: ES ≥ 0.39, p ≤ 0.007; Machine-based: ES ≥ 0.31, p ≤ 0.003). Additionally, the machine-based group meaningfully enhanced upper limb anaerobic power (ES = 0.41, p = 0.021), whereas the free-weight group significantly improved the change of direction (ES = -0.54, p = 0.003) and 2/6 balance conditions analyzed (p ≤ 0.012). Changes in sprint capacity (ES ≥ -0.13, p ≥ 0.274), fascicle length, and pennation angle (ES ≤ 0.19, p ≥ 0.129) were not significant for either training modality. CONCLUSION: Adaptations in athletic performance and muscle architecture would not be meaningfully influenced by the resistance modality trained.

Velocity-Based Method in Free-Weight and Machine-Based Training Modalities: The Degree of Freedom Matters.

ABSTRACT: Hernández-Belmonte, A, Buendía-Romero, Á, Pallares, JG, and Martínez-Cava, A. Velocity-based method in free-weight and machine-based training modalities: the degree of freedom matters. J Strength Cond Res 37(9): e500-e509, 2023-This study aimed to analyze and compare the load-velocity relationships of free-weight and machine-based modalities of 4 resistance exercises. Moreover, we examined the influence of the subject's strength level on these load-velocity relationships. Fifty men completed a loading test in the free-weight and machine-based modalities of the bench press, full squat, shoulder press, and prone bench pull exercises. General and individual relationships between relative intensity (%1RM) and velocity variables were studied through the coefficient of determination ( R2 ) and standard error of the estimate ( SEE ). Moreover, the velocity attained to each %1RM was compared between both modalities. Subjects were divided into stronger and weaker to study whether the subject's strength level influences the mean test (mean propulsive velocity [MPV Test ]) and 1RM (MPV 1RM ) velocities. For both modalities, very close relationships ( R2 ≥ 0.95) and reduced estimation errors were found when velocity was analyzed as a dependent ( SEE ≤ 0.086 m·s -1 ) and independent ( SEE ≤ 5.7% 1RM) variable concerning the %1RM. Fits were found to be higher ( R2 ≥ 0.995) for individual load-velocity relationships. Concerning the between-modality comparison, the velocity attained at each intensity (from 30 to 100% 1RM) was significantly faster for the free-weight variant. Finally, nonsignificant differences were found when comparing MPV Test (differences ≤ 0.02 m·s -1 ) and MPV 1RM (differences ≤ 0.01 m·s -1 ) between stronger and weaker subjects. These findings prove the accuracy and stability of the velocity-based method in the free-weight and machine-based variants but highlight the need to use the load-velocity relationship (preferably the individual one) specific to each training modality.

Is the Record Power Profile Repeatable? A Practical Analysis and Interpretation in Professional Cyclists.

ABSTRACT: Muriel, X, Hernández-Belmonte, A, Mateo-March, M, Valenzuela, PL, Zabala, M, Barranco-Gil, D, Lucia, A, and Pallares, JG. Is the record power profile repeatable? A practical analysis and interpretation in professional cyclists. J Strength Cond Res 37(5): 1131-1134, 2023-This study assessed the repeatability of the Record Power Profile (RPP, i.e., the highest power output that a cyclist can attain for different effort durations under field-based conditions). We registered the RPP of 12 professional cyclists (age 32 ± 5 years) for efforts lasting between 30 seconds and 60 minutes during 3 periods of a season, each of 23-day duration: preparation (including training data only), specific (training and competition data), and competition (competition data only) periods. Repeatability was assessed using the highest 2 (RPP 2 ), 3 (RPP 3 ), and 5 (RPP 5 ) values of mean maximum power obtained by the cyclists for each effort duration in each of the 3 periods. Smaller standard errors of measurement ( SEM ) were found as the competitive period approached, especially for short-duration efforts (i.e., 30 seconds, 1 minute, and 5 minutes, where SEM ranged from 4.3 to 12.5%, 4.1-8.5%, and 2.6-7.0% in the preparation, specific, and competition periods, respectively). However, similar SEM values were found in the 3 periods for RPP 2 , RPP 3 , or RPP 5. In conclusion, the RPP appears as a repeatable parameter for monitoring field-based performance within the different phases of the season in professional cyclists.

Field-Derived Maximal Power Output in Cycling: An Accurate Indicator of Maximal Performance Capacity?

PURPOSE: To determine the validity of field-derived mean maximum power (MMP) values for monitoring maximal cycling endurance performance. METHODS: Twenty-seven male professional cyclists performed 3 timed trials (TTs) of 1-, 5-, and 20-minute duration that were used as the gold standard reference. Field-based power output data (3336 files; 124 [25] per cyclist) were registered during the preparatory (60 d pre-TT, including training data only) and specific period of the season (60 d post-TT, including both training and competitions). Comparisons were made between TT performance (mean power output) and MMP values obtained for efforts of the same duration as TT (MMP of 1-, 5-, and 20-min duration). The authors also compared TT- and MMP-derived values of critical power (CP) and anaerobic work capacity. RESULTS: A large correlation (P < .001, r > .65) was found between MMP and TT performance regardless of the effort duration or season period. However, considerable differences (P < .05, standard error of measurement [SEM] > 5%) were found between MMP and TT values for all effort durations in the preparatory period, as well as for the derived CP and anaerobic work capacity. Significant differences were also found between MMP and TT of 1 minute in the specific period, as well as for anaerobic work capacity, yet with no differences for MMP of 5- and 20-minute duration or the derived CP (P > .05, SEM < 5%). CONCLUSION: MMP values (for efforts ≥5 min) and the associated CP obtained from both training sessions and competitions can be considered overall accurate indicators of the cyclist's maximal capabilities, but specific tests might be necessary for shorter efforts or when considering training sessions only.

The 2-Point Method: A Quick, Accurate, and Repeatable Approach to Estimate Ultrasound-Derived Quadriceps Femoris Cross-Sectional Area.

PURPOSE: To analyze the feasibility of the 2-point method for estimating ultrasound-derived quadriceps femoris cross-sectional area (QUADACSA). First, (1) the agreement between QUADACSA measured by panoramic ultrasound and magnetic resonance imaging (MRI) was studied, and thereafter, we examined 2 approaches of the 2-point method in terms of (2) estimation errors and (3) test-retest repeatability. METHODS: Both thighs of 16 young men were analyzed. Ultrasound-QUADACSA versus MRI-QUADACSA comparison was conducted at 6 thigh lengths (20%-70% of the thigh length). Thereafter, ultrasound-QUADACSA corresponding to 30% and 60% (2-point30%-60%) or 20% and 70% (2-point20%-70%) were used to estimate QUADACSA of the remaining regions. Estimated QUADACSA resulting from both 2-point approaches was compared with the measured one. Finally, the test-retest repeatability was examined by comparing the errors generated on 2 separate estimations. Statistics included the standard error of measurement (SEM) expressed in absolute (in square centimeters) and relative terms (in percentage) as a coefficient of variation (CV), as well as the intraclass correlation cofficient (ICC) and bias. RESULTS: An excellent agreement (ICC ≥ 0.980) and reduced errors (SEM ≤ 2.43 cm2) resulted from the ultrasound-QUADACSA versus MRI-QUADACSA comparison. Although estimation errors found were reduced (CV ≤ 7.50%), they proved to be lower and less biased for the 2-point30%-60%, especially at the central regions (SEM ≤ 2.01 cm2; bias ≤ 0.89 cm2). Similarly, repeatability analysis revealed lower test-retest errors for the 2-point30%-60% (CV ≤ 1.9%) than for the 2-point20%-70% (CV ≤ 4.6%). CONCLUSION: The 2-point method, especially that implemented using the 30% and 60% regions, represents an accurate and repeatable strategy to evaluate QUADACSA.

Accuracy and reliability of inertial devices for load assessment during flywheel workout / Precisión y confiabilidad de los dispositivos inerciales para la evaluación de la carga durante entrenamiento con polea cónica

Abstract There is currently an increase in inertial flywheel application in strength training; thus, it must be monitored by an accurate and reliable device. The present study tested: (1) the accuracy of an inertial measurement device (IMU) to correctly measure angular velocity and (2) its inter-unit reliability for the measurement of external load. The analysis was performed using Pearson Correlation and Intraclass Correlation Coefficient (ICC). The IMU accuracy was tested using Bland-Altman and the reliability with the coefficient of variation (CV). Ten elite-level football players performed ten series of 5 repetitions in a one-hand standing row exercise (5 series with each arm). A nearly perfect accuracy (ICC=.999) and a very good between-device reliability (Bias=-.010; CV=.017%) was found. IMU is a reliable and valid device to assess angular velocity in inertial flywheel workout objectively.

Resumen Actualmente, hay un aumento en la utilización de la polea cónica en el entrenamiento de fuerza; por lo tanto, es necesario monitorearlo con un dispositivo preciso y confiable. El presente estudio probó: (1) la precisión de un dispositivo de medición inercial (IMU), para medir correctamente la velocidad angular y (2) su confiabilidad entre unidades para la medición de carga externa. El análisis se realizó utilizando la correlación de Pearson y el Coeficiente de Correlación Intra-clase (CCI). La precisión de la IMU se probó usando Bland-Altman y la confiabilidad con el Coeficiente de Variación (CV). Diez jugadores de fútbol de nivel élite realizaron 10 series de 5 repeticiones en un ejercicio de fila de pie con una mano (5 series con cada brazo). Se encontró una precisión casi perfecta (ICC = .999) y una muy buena confiabilidad entre dispositivos (Sesgo = -. 010; CV = .017%). IMU´s es un dispositivo confiable y válido para evaluar objetivamente la velocidad angular en el entrenamiento inercial de la polea cónica.

Resumo Atualmente, há um aumento na utilização da polia cônica no treinamento de força; portanto, é necessário monitorá-lo com um dispositivo preciso e confiável. O presente estudo testou: (1) a precisão de um dispositivo de medição inercial (IMU), para medir corretamente a velocidade angular e (2) sua confiabilidade interunidades para medição de carga externa. A análise foi realizada por meio da correlação de Pearson e do Coeficiente de Correlação Intraclasse (ICC). A precisão do IMU foi testada usando Bland-Altman e a confiabilidade com o Coeficiente de Variação (CV). Dez jogadores de futebol de elite realizaram 10 séries de 5 repetições em um exercício de linha em pé com uma mão (5 séries com cada braço). Foi encontrado uma precisão quase perfeita (ICC = 0,999) e confiabilidade entre dispositivos muito boa (Bias = - 0,010; CV = 0,017%). IMU's é um dispositivo confiável e válido para avaliar objetivamente a velocidade angular no treinamento inercial da polia cônica.

Strength and Athletic Adaptations Produced by 4 Programming Models: A Velocity-Based Intervention Using a Real-Context Routine.

PURPOSE: To compare the strength and athletic adaptations induced by 4 programming models. METHODS: Fifty-two men were allocated into 1 of the following models: linear programming (intensity increased while intraset volume decreased), undulating programming (intensity and intraset volume were varied in each session or set of sessions), reverse programming (intensity decreased while intraset volume increased), or constant programming (intensity and intraset volume kept constant throughout the training plan). All groups completed a 10-week resistance-training program made up of the free-weight bench press, squat, deadlift, prone bench pull, and shoulder press exercises. The 4 models used the same frequency (2 sessions per week), number of sets (3 per exercise), interset recoveries (4 min), and average intensity throughout the intervention (77.5%). The velocity-based method was used to accurately adjust the planned intensity for each model. RESULTS: The 4 programming models exhibited significant pre-post changes in most strength variables analyzed. When considering the effect sizes for the 5 exercises trained, we observed that the undulating programming (mean effect size = 0.88-2.92) and constant programming (mean effect size = 0.61-1.65) models induced the highest and lowest strength enhancements, respectively. Moreover, the 4 programming models were found to be effective to improve performance during shorter (jump and sprint tests) and longer (upper- and lower-limb Wingate test) anaerobic tasks, with no significant differences between them. CONCLUSION: The linear, undulating, reverse, and constant programming models are similarly effective to improve strength and athletic performance when they are implemented in a real-context routine.

Panoramic ultrasound requires a trained operator and specific evaluation sites to maximize its sensitivity: A comprehensive analysis of the measurement errors.

This study aimed to examine the validity and repeatability of panoramic ultrasound to evaluate the anatomical cross-sectional area (ACSA) of quadriceps femoris muscles. Specifically, we aimed to quantify the errors generated during the image acquisition and analysis (repeatability), as well as when comparing with magnetic resonance imaging (MRI) (validity). Moreover, we analyzed the influence of the operator's experience and the region of the thigh, on these errors. Both thighs of 16 subjects were included. The validity and repeatability study quantified the errors made by two operators (trained and novice) when measuring ACSA of vastus lateralis (VL), vastus medialis-intermedius (VMVI), and rectus femoris (RF), in six thigh regions (from 20 to 70%). Two ACSA images were acquired 5 min apart to examine acquisition errors, whereas acquisition #1 was analyzed twice to quantify analysis errors. Thereafter, ACSA of acquisition #1 was compared with that measured by MRI. Statistics included the standard error of measurement (SEM) expressed in absolute (cm2) and relative terms (%) as a coefficient of variation (CV). Measurement errors were lower for the trained operator than for the novice: Acquisition (SEM = 0.05 - 0.78 vs. 0.25 - 1.42 cm2), analysis (SEM = 0.13 - 1.93 vs. 0.30 - 3.05 cm2) and compared-with-MRI (SEM = 0.13 - 1.93 vs. 0.30 - 3.05 cm2). Regions with the lowest errors were those located at the middle of the thigh (40-50%), although slight between-muscle differences were found: VMVI (30-40%), VL (40-50%), RF (50-60%). These findings suggest that the accurate implementation of panoramic ultrasound to measure ACSA of quadriceps femoris muscles requires a trained operator and specific evaluation sites.

Bench Press at Full Range of Motion Produces Greater Neuromuscular Adaptations Than Partial Executions After Prolonged Resistance Training.

ABSTRACT: Martínez-Cava, A, Hernández-Belmonte, A, Courel-Ibáñez, J, Morán-Navarro, R, González-Badillo, JJ, and Pallarés, JG. Bench press at full range of motion produces greater neuromuscular adaptations than partial executions after prolonged resistance training. J Strength Cond Res 36(1): 10-15, 2022-Training at a particular range of motion (ROM) produces specific neuromuscular adaptations. However, the effects of full and partial ROM in one of the most common upper-limb exercises such as the bench press (BP) remain controversial. In this study, 50 recreationally to highly resistance trained men were randomly assigned to 1 of 4 training groups: full bench press (BPFULL), two-thirds bench press (BP2/3), and one-third bench press (BP1/3) and control (training cessation). Experimental groups completed a 10-week velocity-based resistance training program using the same relative load (linear periodization, 60-80% 1 repetition maximum [1RM]), only differing in the ROM trained. Individual ROM for each BP variation was determined in the familiarization and subsequently replicated in every lift during training and testing sessions. Neuromuscular adaptations were evaluated by 1RM strength and mean propulsive velocity (MPV). The BPFULL group obtained the best results for the 3 BP variations (effect size [ES] = 0.52-1.96); in turn, partial BP produced smaller improvements as the ROM decreased (BP2/3: ES = 0.29-0.78; BP1/3: ES = -0.01 to 0.66). After 10-week of training cessation, the control group declined in all neuromuscular parameters (ES = 0.86-0.92) except in MPV against low loads. Based on these findings, the BPFULL stands as the most effective exercise to maximize neuromuscular improvements in recreational and well-trained athletes compared with partial ROM variations.

Level of Effort: A Reliable and Practical Alternative to the Velocity-Based Approach for Monitoring Resistance Training.

ABSTRACT: Hernández-Belmonte, A, Courel-Ibáñez, J, Conesa-Ros, E, Martínez-Cava, A, and Pallarés, JG. Level of effort: A reliable and practical alternative to the velocity-based approach for monitoring resistance training. J Strength Cond Res 36(11): 2992-2999, 2022-This study analyzed the potential of the level of effort methodology as an accurate indicator of the programmed relative load (percentage of one-repetition maximum [%1RM]) and intraset volume of the set during resistance training in the bench press, full squat, shoulder press, and prone bench pull exercises, through 3 specific objectives: (a) to examine the intersubject and intrasubject variability in the number of repetitions to failure ( n RM) against the actual %1RM lifted (adjusted by the individual velocity), (b) to investigate the relationship between the number of repetitions completed and velocity loss reached, and (c) to study the influence of the subject's strength level on the aforementioned parameters. After determining their individual load-velocity relationships, 30 subjects with low ( n = 10), medium ( n = 10), and high ( n = 10) relative strength levels completed 2 rounds of n RM tests against their 65, 75, 85, and 95% 1RM in the 4 exercises. The velocity of all repetitions was monitored using a linear transducer. Intersubject and intrasubject variability analyses included the 95% confidence intervals (CIs) and the the standard error of measurement ( SEM ), respectively. Coefficient of determination (R 2 ) was used as the indicator of relationship. n RM showed a limited intersubject (CI ≤ 4 repetitions) and a very low intrasubject ( SEM ≤1.9 repetitions) variability for all the strength levels, %1RM, and exercises analyzed. A very close relationship ( R2 ≥ 0.97) between the number of repetitions completed and the percentage of velocity loss reached (from 10 to 60%) was found. These findings strengthen the level of effort as a reliable, precise, and practical strategy for programming resistance training.

Reproducibility of the Rotor 2INpower Crankset for Monitoring Cycling Power Output: A Comprehensive Analysis in Different Real-Context Situations.

PURPOSE: To examine the reproducibility (intradevice and interdevice agreement) of the Rotor 2INpower device under a wide range of cycling conditions. METHODS: Twelve highly trained male cyclists and triathletes completed 5 cycling tests, including graded exercise tests at different cadences (70-100 rpm), workloads (100-650 W), pedaling positions (seated and standing), and vibration conditions (20-40 Hz) and an 8-second maximal sprint (>1000 W). An intradevice analysis included a comparison between the power output registered by 3 units of Rotor 2INpower, whereas the power output provided by each one of these units and the gold-standard SRM crankset were compared for the interdevice analysis. Among others, statistical calculations included the standard error of measurement, expressed in absolute (in watts) and relative terms as the coefficient of variation (CV). RESULTS: Except for the graded exercise test seated at 100 rpm/100 W (CV = 10.2%), the intradevice analysis showed an acceptable magnitude of error (CV ≤ 6.9%, standard error of measurement ≤ 12.3 W) between the 3 Rotor 2INpower. Similarly, these 3 units showed an acceptable agreement with the gold standard in all graded exercise test situations (CV ≤ 4.0%, standard error of measurement ≤ 13.1 W). On the other hand, both the intradevice and interdevice agreements proved to be slightly reduced under high cadences (intradevice: CV ≤ 10.2%; interdevice: CV ≤ 4.0%) and vibration (intradevice: CV ≤ 4.0%; interdevice: CV ≤ 3.6%), as well as during standing pedaling (intradevice: CV ≤ 4.1%; interdevice: CV ≤ 2.5%). Although within the limits of an acceptable agreement, measurement errors increased during the sprint tests (CV ≤ 7.4%). CONCLUSIONS: Based on these results, the Rotor 2INpower could be considered a reproducible tool to monitor power output in most cycling situations.

Pectoralis Cross-Sectional Area can be Accurately Measured using Panoramic Ultrasound: A Validity and Repeatability Study.

The objective of the current study was to examine the validity and repeatability of panoramic ultrasound in evaluating the anatomical cross-sectional area (ACSA) of the pectoralis major. Specifically, we aimed to quantify the measurement errors generated during the image acquisition and analysis (repeatability), as well as when comparing with magnetic resonance imaging (MRI) (validity). Moreover, we aimed to analyze the influence of the operator's experience on these measurement errors. Both sides of the chest of 16 participants (n = 32) were included. Errors made by two operators (trained and novice) when measuring pectoralis major ACSA (50% of sternum-areola mammae distance) were examined. Acquisition errors included the comparison of two images acquired 5 min apart. Acquisition 1 was analyzed twice to quantify analysis errors. Thereafter, acquisition 1 was compared with MRI. Statistics include the standard error of measurement (SEM), expressed in absolute (cm2) and relative (%) terms as a coefficient of variation (CV), and the calculation of systematic bias. Errors made by the trained operator were lower than those made by the novice, especially during the image acquisition (SEM = 0.25 vs. 0.66 cm2, CV = 1.06 vs. 2.98%) and when compared with MRI (SEM = 0.27 vs. 1.90 cm2, CV = 1.13 vs. 8.16%). Furthermore, although both operators underestimated the ACSA, magnitude and variability [SD] of these errors were lower for the trained operator (bias = -0.19 [0.34] cm2) than for the novice (bias = -1.97 [2.59] cm2). Panoramic ultrasound is a valid and repeatable technique for measuring pectoralis major ACSA, especially when implemented by a trained operator.

Isometric knee extension test: A practical, repeatable, and suitable tool for lower-limb screening among institutionalized older adults.

We aimed to analyze the isometric knee extension test (IKE) test in terms of i) intra- and inter-session repeatability, and ii) relationship with functional and body composition factors of sarcopenia among institutionalized older adults. Thirteen institutionalized older adults (age = 87 ± 10 years, body mass [BM] = 73.1 ± 10.9 kg, body mass index [BMI] = 28.5 ± 3.8 kg·m2) were recruited from a nursing home. Variability of maximal isometric force registered in three IKE trials performed on the same day was used to examine intra-session repeatability, whereas inter-session repeatability was analyzed by comparing maximal isometric force from two different days. Furthermore, functional (Handgrip, 6-m Gait Speed, Time Up and Go [TUG], and Sit-to-stand tests) and body composition (appendicular lean mass adjusted by BMI, ALM/BMI) evaluations were conducted. Statistics included the intraclass correlation coefficient (ICC) and the standard error of measurement (SEM), expressed in both absolute (N·kg-1) and relative terms (coefficient of variation, CV = 100 × SEM / mean). High to very high intra-session repeatability was found for both the dominant and non-dominant legs (CV ≤ 6.0%, ICC ≥ 0.989). Similarly, both legs showed high inter-session repeatability (SEM ≤ 0.26 N·kg-1, ICC ≥ 0.959). On the other hand, significant relationships were found between Dominant and Non-dominant IKE tests and 6-m Gait Speed (r = 0.77; r = 0.58), ALM/BMI (r = 0.62; r = 0.58), and Non-dominant Handgrip/BM (r = 0.60; r = 0.68). In addition, a significant association was found between Dominant IKE/BM and TUG (r = -0.74), as well as between Non-dominant IKE/BM and Dominant Handgrip/BM (r = 0.67). These findings suggest that the IKE test is a repeatable and suitable strategy for lower-limb screening in institutionalized older adults.

Effects of range of motion on resistance training adaptations: A systematic review and meta-analysis.

BACKGROUND: Nowadays, there is a lack of consensus and high controversy about the most effective range of motion (ROM) to minimize the risk of injury and maximize the resistance training adaptations. OBJECTIVE: To conduct a systematic review and meta-analysis of the scientific evidence examining the effects of full and partial ROM resistance training interventions on neuromuscular, functional, and structural adaptations. METHODS: The original protocol (CRD42020160976) was prospectively registered in the PROSPERO database. Medline, Scopus, and Web of Science databases were searched to identify relevant articles from the earliest record up to and including March 2021. The RoB 2 and GRADE tools were used to judge the level of bias and quality of evidence. Meta-analyses were performed using robust variance estimation with small-sample corrections. RESULTS: Sixteen studies were finally included in the systematic review and meta-analyses. Full ROM training produced significantly greater adaptations than partial ROM on muscle strength (ES = 0.56, p = 0.004) and lower-limb hypertrophy (ES = 0.88, p = 0.027). Furthermore, although not statistically significant, changes in functional performance were maximized by the full ROM training (ES = 0.44, p = 0.186). Finally, no significant superiority of either ROM was found to produce changes in muscle thickness, pennation angle, and fascicle length (ES = 0.28, p = 0.226). CONCLUSION: Full ROM resistance training is more effective than partial ROM to maximize muscle strength and lower-limb muscle hypertrophy. Likewise, functional performance appears to be favored by the use of full ROM exercises. On the contrary, there are no large differences between the full and partial ROM interventions to generate changes in muscle architecture.