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Seiichiro Takei, Kuniaki Hirayama and Junichi Okada

. Thus, the aim of the present study was to investigate the factors determining the optimum load for maximal power output during HPCs in Olympic weight lifters. We tested 2 hypotheses: (1) a decrease in velocity leads to a decrease in power output at loads above the optimal loads reported in previous

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Pedro Jiménez-Reyes, Amador García-Ramos, Victor Cuadrado-Peñafiel, Juan A. Párraga-Montilla, José A. Morcillo-Losa, Pierre Samozino and Jean-Benoît Morin

can be determined with the use of affordable devices such as radar guns or mobile applications, and the outcomes of the F–V profile (ie, maximal theoretical force [ F 0 ], maximal theoretical velocity [ V 0 ], F–V slope, and maximal power [ P max ]) can be used to implement individualized training

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Jeroen Vrints, Erwin Koninckx, Marc Van Leemputte and Ilse Jonkers

Saddle position affects mechanical variables during submaximal cycling, but little is known about its effect on mechanical performance during maximal cycling. Therefore, this study relates saddle position to experimentally obtained maximal power output and theoretically calculated moment generating capacity of hip, knee and ankle muscles during isokinetic cycling. Ten subjects performed maximal cycling efforts (5 s at 100 rpm) at different saddle positions varying ± 2 cm around the in literature suggested optimal saddle position (109% of inner leg length), during which crank torque and maximal power output were determined. In a subgroup of 5 subjects, lower limb kinematics were additionally recorded during submaximal cycling at the different saddle positions. A decrease in maximal power output was found for lower saddle positions. Recorded changes in knee kinematics resulted in a decrease in moment generating capacity of biceps femoris, rectus femoris and vastus intermedius at the knee. No differences in muscle moment generating capacity were found at hip and ankle. Based on these results we conclude that lower saddle positions are less optimal to generate maximal power output, as it mainly affects knee joint kinematics, compromising mechanical performance of major muscle groups acting at the knee.

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Thomas Korff, Ann H. Newstead, Renate van Zandwijk and Jody L. Jensen

The purpose of this study was to examine the interactions between aging, activity levels and maximal power production during cycling. Participants were divided into younger adults (YA), older active adults (OA,) and older sedentary adults (OS). Absolute maximum power was significantly greater in YA compared with OS and OA; no differences were found between OA and OS. The age-related difference in maximum power was accompanied by greater absolute peak knee extension and knee flexion powers. Relative joint power contributions revealed both age- and activity-related differences. YA produced less relative hip extension power than older adults, regardless of activity level. The OS participants produced less relative knee flexion power than active adults, regardless of age. The results show the age-related decline in muscular power production is joint specific and that activity level can be a modifier of intersegmental coordination, which has implications for designing interventions for the aging population.

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Simon Avrillon, Boris Jidovtseff, François Hug and Gaël Guilhem

Purpose:

Muscle strengthening is commonly based on the use of isoinertial loading, whereas variable resistances such as pneumatic loading may be implemented to optimize training stimulus. The purpose of the current study was to determine the effect of the ratio between pneumatic and isoinertial resistance on the force–velocity relationship during ballistic movements.

Methods:

A total of 15 participants performed 2 concentric repetitions of ballistic bench-press movements with intention to throw the bar at 30%, 45%, 60%, 75%, and 90% of the maximal concentric repetition with 5 resistance ratios including 100%, 75%, 50%, 25%, or 0% of pneumatic resistance, the additional load being isoinertial. Force-, velocity-, and power-time patterns were assessed and averaged over the concentric phase to determine the force–velocity and power–velocity relationships for each resistance ratio.

Results:

Each 25% increase in the pneumatic part in the resistance ratio elicited higher movement velocity (+0.11 ± 0.03 m/s from 0% to 80% of the concentric phase) associated with lower force levels (–43.6 ± 15.2 N). Increased isoinertial part in the resistance ratio resulted in higher velocity toward the end of the movement (+0.23 ± 0.01 m/s from 90% to 100%).

Conclusions:

The findings show that the resistance ratio could be modulated to develop the acceleration phase and force toward the end of the concentric phase (pneumatic-oriented resistance). Inversely, isoinertial-oriented resistance should be used to develop maximal force and maximal power. Resistance modality could, therefore, be considered an innovative variable to modulate the training stimulus according to athletic purposes.

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Abderrahmane Rahmani, Pierre Samozino, Jean-Benoit Morin and Baptiste Morel

) was also considered for further analysis. Values of maximal power of the power–velocity relationship (P max ) were calculated as previously validated 14 , 23 : P max = F 0 × v 0 4 (5) Statistical Analysis All calculations were performed with a custom-written software program (Microsoft Excel

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Caroline Giroux, Giuseppe Rabita, Didier Chollet and Gaël Guilhem

Performance during human movements is highly related to force and velocity muscle capacities. Those capacities are highly developed in elite athletes practicing power-oriented sports. However, it is still unclear whether the balance between their force and velocity-generating capacities constitutes an optimal profile. In this study, we aimed to determine the effect of elite sport background on the force–velocity relationship in the squat jump, and evaluate the level of optimization of these profiles. Ninetyfive elite athletes in cycling, fencing, taekwondo, and athletic sprinting, and 15 control participants performed squat jumps in 7 loading conditions (range: 0%–60% of the maximal load they were able to lift). Theoretical maximal power (Pm), force (F 0), and velocity (v 0) were determined from the individual force–velocity relationships. Optimal profiles were assessed by calculating the optimal force (F 0th) and velocity (v 0th). Athletic sprinters and cyclists produced greater force than the other groups (P < .05). F 0 was significantly lower than F 0th, and v 0 was significantly higher than v 0th for female fencers and control participants, and for male athletics sprinters, fencers, and taekwondo practitioners (P < .05). Our study shows that the chronic practice of an activity leads to differently balanced force–velocity profiles. Moreover, the differences between measured and optimal force–velocity profiles raise potential sources of performance improvement in elite athletes.

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Pierre Samozino, Jean Romain Rivière, Jérémy Rossi, Jean-Benoit Morin and Pedro Jimenez-Reyes

The ability to perform ballistic muscle contractions, as during jumps, changes of direction, and first step of a sprint, is determinant in numerous sport activities (team sports, track and field, and martial arts). It depends on both the maximal power output (relative to body mass) lower limbs can

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John Garhammer

Films taken at the first Women’s World Weightlifting Championship were analyzed to determine the average power output during the total pulling phase, and the second pull phase, for the heaviest successful snatch and clean lift of gold medalists in each of nine body-weight divisions. Comparisons were made with previously published data on power output by male lifters in World and Olympic competition. Average relative power output values were one and a half to two times greater for both men and women when only the second pull phase of each lift was analyzed. Results show that women can generate higher short-term power outputs than previously documented, but lower than for men in absolute values and relative to body mass. Male/female comparisons in other high power sport events and basic strength measures are discussed. The high power outputs suggest the value of including the types of lifts analyzed in training programs to improve short-term power output.

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Oliver Gonzalo-Skok, Julio Tous-Fajardo, José Luis Arjol-Serrano, Luis Suarez-Arrones, José Antonio Casajús and Alberto Mendez-Villanueva

Purpose:

To examine the effects of a low-volume repeated-power-ability (RPA) training program on repeated-sprint and changeof-direction (COD) ability and functional jumping performance.

Methods:

Twenty-two male elite young basketball players (age 16.2 ± 1.2 y, height 190.0 ± 10.0 cm, body mass 82.9 ± 10.1 kg) were randomly assigned either to an RPA-training group (n = 11) or a control group (n = 11). RPA training consisted of leg-press exercise, twice a week for 6 wk, of 1 or 2 blocks of 5 sets × 5 repetitions with 20 s of passive recovery between sets and 3 min between blocks with the load that maximized power output. Before and after training, performance was assessed by a repeated-sprint-ability (RSA) test, a repeated-COD-ability test, a hop for distance, and a drop jump followed by tests of a double unilateral hop with the right and left legs.

Results:

Within-group and between-groups differences showed substantial improvements in slowest (RSAs) and mean time (RSAm) on RSA; best, slowest and mean time on repeated-COD ability; and unilateral right and left hop in the RPA group in comparison with control. While best time on RSA showed no improvement in any group, there was a large relationship (r = .68, 90% CI .43;.84) between the relative decrement in RSAm and RSAs, suggesting better sprint maintenance with RPA training. The relative improvements in best and mean repeated-COD ability were very largely correlated (r = .89, 90% CI .77;.94).

Conclusions:

Six weeks of low-volume (4–14 min/wk) RPA training improved several physical-fitness tests in basketball players.