Victor Tella

Concentric and Impact Forces of Single-Leg Jumps in an Aquatic Environment versus on Land

PURPOSE This study investigated the kinetic and the kinematic differences in female athletes in single-leg static jumps in an aquatic environment compared with those performed on dry land. METHODS Twelve healthy, junior national team handball players participated. Subjects completed a familiarization and a testing session. The subjects performed a series of single-leg jumps, dry land and aquatic with and without devices, which were randomized to avoid fatigue effects. Peak concentric force, rate of force development, impact force, and time of the jumps were determined using a force plate. RESULTS Peak concentric force and rate of force development were significantly (P < 0.05) higher in the aquatic jumps, whereas impact force was significantly (P < 0.05) lower. There was a shorter total jump time (P < 0.05) for the aquatic jump without devices, whereas the time required to reach peak force was not significantly different between the two environments, despite the greater resistance to movement in the aquatic medium. DISCUSSION Aquatic jump exercises result in greater force production and rate of force development in the same amount of time with less impact and can thus offer a viable alternative to traditional dry-land jump exercises, which may also be beneficial for rehabilitating or aging populations. The benefits of this type of exercise include an exercise mode that can be performed without compromising speed while reducing the potential for joint injury.

Discriminatory power of water polo game-related statistics at the 2008 Olympic Games

Abstract The aims of this study were (1) to compare water polo game-related statistics by context (winning and losing teams) and sex (men and women), and (2) to identify characteristics discriminating the performances for each sex. The game-related statistics of the 64 matches (44 mens and 20 womens) played in the final phase of the Olympic Games held in Beijing in 2008 were analysed. Unpaired t-tests compared winners and losers and men and women, and confidence intervals and effect sizes of the differences were calculated. The results were subjected to a discriminant analysis to identify the differentiating game-related statistics of the winning and losing teams. The results showed the differences between winning and losing mens teams to be in both defence and offence, whereas in womens teams they were only in offence. In mens games, passing (assists), aggressive play (exclusions), centre position effectiveness (centre shots), and goalkeeper defence (goalkeeper-blocked 5-m shots) predominated, whereas in womens games the play was more dynamic (possessions). The variable that most discriminated performance in men was goalkeeper-blocked shots, and in women shooting effectiveness (shots). These results should help coaches when planning training and competition.

Effects of a Short-Term Aquatic Resistance Program on Strength and Body Composition in Fit Young Men

Colado, JC, Tella, V, Triplett, NT, and González, LM. Effects of a short-term aquatic resistance program on strength and body composition in fit young men. J Strength Cond Res 23(2): 549-559, 2009-This study was designed to analyze the effects of a short-term periodized aquatic resistance program (PARP) on upper-limb maximum strength, leg muscular power, and body composition (BC) in fit young men. Twenty subjects (21.2 ± 1.17 years) were randomly assigned to an exercise or control group; 12 subjects completed the study. The aquatic exercise group (AEG; n = 7) participated in an 8-week supervised program of 3 d·wk−1, and the control group (CG; n = 5) maintained their regular activities. The PARP consisted of a total-body resistance exercise workout using aquatic devices that increased drag force, with a cadence of movement controlled and adjusted individually for each exercise and subject. The volume and intensity of the program were increased progressively. Submaximal tests were carried out to determine the change in upper-limb maximum strength, as well as a squat-jump test to determine the change in leg muscular power. Four skinfold sites, 6 circumference sites, body weight, and stature were used to determine changes in BC. A significant increase in upper-limb maximum strength and leg muscular power was observed for the AEG. A significant increase also was noted in the circumference and muscular area of the arm, and there were significant decreases in pectoral and abdominal skinfolds. Nevertheless, the circumference, muscular area, and local fat of the lower limbs did not change. There were no significant changes in any variables in the CG. These results indicate that the PARP produces significant improvements in muscular strength, power, and fat-free mass and, thus, seems to be a very effective form of resistance exercise.

A Method for Monitoring Intensity During Aquatic Resistance Exercises

Colado, JC, Tella, V, and Triplett, NT. A method for monitoring intensity during aquatic resistance exercises. J Strength Cond Res 22(6): 2045-2049, 2008-The aims of this study were (i) to check whether monitoring of both the rhythm of execution and the perceived effort is a valid tool for reproducing the same intensity of effort in different sets of the same aquatic resistance exercise (ARE) and (ii) to assess whether this method allows the ARE to be put at the same intensity level as its equivalent carried out on dry land. Four healthy trained young men performed horizontal shoulder abduction and adduction (HSAb/Ad) movements in water and on dry land. Muscle activation was recorded using surface electromyography of 1 stabilizer and several agonist muscles. Before the final tests, the ARE movement cadence was established individually following a rhythmic digitalized sequence of beats to define the alternate HSAb/Ad movements. This cadence allowed the subject to perform 15 repetitions at a perceived exertion of 9-10 using Hydro-Tone Bells. After that, each subject performed 2 nonconsecutive ARE sets. The dry land exercises (1 set of HSAb and 1 set of HSAd) were performed using a dual adjustable pulley cable motion machine, with the previous selection of weights that allowed the same movement cadence to be maintained and the completion of the same repetitions in each of the sets as with the ARE. The average normalized data were compared for the exercises in order to determine possible differences in muscle activity. The results show the validity of this method for reproducing the intensity of effort in different sets of the same ARE, but is not valid for matching the same intensity level as kinematically similar land-based exercises.

Concurrent validation of the OMNI-resistance exercise scale of perceived exertion with Thera-band resistance bands.

Abstract Colado JC, Garcia-Masso X, Triplett TN, Flandez J, Borreani S, Tella V. Concurrent validation of the OMNI-Resistance Exercise Scale of perceived exertion with Thera-Band resistance bands. J Strength Cond Res 26(11): 3018–3024, 2012—The concurrent validity of the OMNI-Resistance Exercise Scale (OMNI-RES) of perceived exertion for use with elastic bands was studied during isotonic resistance exercises. Twenty healthy, physically active subjects completed both familiarization and testing sessions. The criterion variables were myoelectric activity, recorded by electromyography, and heart rate, recorded by a heart rate monitor. The subjects performed 2 separate sets of 15 repetitions in each of the 2 testing sessions and for each of the exercises applied (i.e., frontal and lateral raises). One set was carried out with the separation between the hands gripping the elastic band allowing that 15 repetition maximum to be performed in the selected exercise, whereas the other set was carried out with the separation between hands at +50% of the previous grip. The perceived exertion rating for the active muscles and for the overall body, muscular activity, and heart rate were measured during the final repetition of each set. The results showed significant differences (p ⩽ 0.001) in myoelectric activity, heart rate, and OMNI-RES scores between the low- and high-intensity sets and the intraclass correlation coefficient was 0.72–0.76. So it can be concluded that the OMNI-RES can be used for monitoring the intensity of exercises when elastic bands are used. This would allow the training stimulus dosage to be precisely controlled in both the session in progress and between different sessions, and allowing to differentiate between different levels of intensity according to the physical aptitudes and special physiological needs of the subjects.

Effects of Aquatic and Dry Land Resistance Training Devices on Body Composition and Physical Capacity in Postmenopausal Women

Effects of Aquatic and Dry Land Resistance Training Devices on Body Composition and Physical Capacity in Postmenopausal Women To determine the effects of a supervised strength training program on body composition and physical capacity of older women using three different devices: weight machines, elastic bands, and aquatic devices that increase drag forces (ADIDF). Four groups were formed: control group, weight machine group (WMG), elastic band group (EBG) and a group that used ADIDF (ADIDFG). Body composition and physical capacity were assessed before and after the intervention period. The ADIDFG showed improvements in fat mass (FM), fat-free mass of the left arm (FFM-LA) and right arm (FFM-RA), knee push-up test (KPT), squat test (ST) and crunch test (CT) (p <0.05). Individuals in the EBG and WMG also improved their FM, fat free mass (FFM), FFM-LA, FFM-RA, KPU, ST and CT. ADIDF training improves body composition and physical capacity of postmenopausal women as does performing land-based training programs.

Myoelectric Activation and Kinetics of Different Plyometric Push-Up Exercises

García-Massó, X, Colado, JC, González, LM, Salvá, P, Alves, J, Tella, V, and Triplett, NT. Myoelectric activation and kinetics of different plyometric push-up exercises. J Strength Cond Res 25(7): 2040-2047, 2011—The kinetic and myoelectric differences between 3 types of plyometric push-ups were investigated. Twenty-seven healthy, physically active men served as subjects and completed both familiarization and testing sessions. During these sessions, subjects performed 2 series of 3 plyometric push-up variations in a counterbalanced order according to the following techniques: Countermovement push-ups (CPUs) were push-ups performed with the maximum speed of movement; jump push-ups (JPUs) were similar to clapping push-ups; and fall push-ups (FPUs) required kneeling subjects to drop and then attempt to return to their initial position. Vertical ground reaction forces were determined by using a force plate. Myoelectric activity was recorded by means of electromyography. Impact force and impact rate of force development were significantly (p < 0.05) higher for FPUs than for JPUs. The maximum rate of force development was higher for CPUs (p < 0.05) than for JPUs, and the maximum force was higher for the CPUs than for the FPUs (p < 0.05). There were differences among exercises for the mean muscle activation of the pectoralis major (PM; p < 0.001), triceps brachii (p < 0.001), external oblique (p < 0.005) and anterior deltoid (p < 0.001), and in the maximum muscle activation of the PM (p < 0.001). Plyometric push-ups with countermovement achieved a higher maximum force and rate of force and did not cause impact forces. Thus, this type of push-up exercise may be regarded as the best for improving explosive force. The FPU exercise achieved higher levels of muscular activation in the agonist and synergist muscle groups, and greater impact forces and impact force development rates.

Exercise intensity progression for exercises performed on unstable and stable platforms based on ankle muscle activation.

Ankle sprains are a common sports injury. The literature focuses on the application of neuromuscular training for the improvement of balance, injury prevention and rehabilitation. However, there is a dearth of knowledge about the appropriate prescription of exercises using unstable platforms and surfaces. The purpose of this study was to devise an ankle rehabilitation or training program with exercise progression based on the extent of muscle activation, employing platforms with different levels of stability and additional resistance. A descriptive study of electromyography (EMG) during ankle exercises was performed with a convenience sample of healthy subjects. Forty-four subjects completed 12 exercises performed in a random order. Exercises were performed unipedally or bipedally with or without elastic tubing as resistance on various unstable (uncontrolled multiaxial and uniaxial movement) and stable surfaces. Surface EMG from the tibialis anterior (TA), peroneus longus (PL) and soleus (SOL) were collected to quantify the amount of muscle activity. Significant differences were found between exercise conditions for PL (p<.001), TA (p=.011), and SOL (p<.001). The greatest EMG activity for all muscles occurred with an upright unipedal stance on a soft stability surface with resistance. The least EMG activity for the TA and SOL were in a seated position and for the PL in an erect bipedal position without resistance. Based on the level of ankle muscle activation, exercises for the ankle should progress from bilateral exercises on exercise balls (lowest intensity), to a unipedal position on a soft surface in combination with elastic tubing (highest intensity) in order to achieve progressively greater ankle muscle activation.

Bench press and push-up at comparable levels of muscle activity results in similar strength gains.

Abstract Calatayud, J, Borreani, S, Colado, JC, Martin, F, Tella, V, and Andersen, LL. Bench press and push-up at comparable levels of muscle activity results in similar strength gains. J Strength Cond Res 29(1): 246–253, 2015—Electromyography (EMG) exercise evaluation is commonly used to measure the intensity of muscle contraction. Although researchers assume that biomechanically comparable resistance exercises with similar high EMG levels will produce similar strength gains over the long term, no studies have actually corroborated this hypothesis. This study evaluated EMG levels during 6 repetition maximum (6RM) bench press and push-up, and subsequently performed a 5-week training period where subjects were randomly divided into 3 groups (i.e., 6RM bench press group, 6RM elastic band push-up group, or control group) to evaluate muscle strength gains. Thirty university students with advanced resistance training experience participated in the 2-part study. During the training period, exercises were performed using the same loads and variables that were used during the EMG data collection. At baseline, EMG amplitude showed no significant difference between 6RM bench press and band push-up. Significant differences among the groups were found for percent change (&Dgr;) between pretest and posttest for 6RM (p = 0.017) and for 1 repetition maximum (1RM) (p < 0.001). Six repetition maximum bench press group and 6RM elastic band push-up group improved their 1RM and 6RM (&Dgr; ranging from 13.65 to 22.21) tests significantly with similar gains, whereas control group remains unchanged. Thus, when the EMG values are comparable and the same conditions are reproduced, the aforementioned exercises can provide similar muscle strength gains.

Differences and discriminatory power of water polo game-related statistics in men in international championships and their relationship with the phase of the competition.

Abstract Escalante, Y, Saavedra, JM, Tella, V, Mansilla, M, García-Hermoso, A, and Domínguez, AM. Differences and discriminatory power of water polo game-related statistics in men in international championships and their relationship with the phase of the competition. J Strength Cond Res 27(4): 893–901, 2013—The aims of this study were (a) to compare water polo game-related statistics by context (winning and losing teams) and phase (preliminary, classification, and semifinal/bronze medal/gold medal), and (b) identify characteristics that discriminate performances for each phase. The game-related statistics of the 230 mens matches played in World Championships (2007, 2009, and 2011) and European Championships (2008 and 2010) were analyzed. Differences between contexts (winning or losing teams) in each phase (preliminary, classification, and semifinal/bronze medal/gold medal) were determined using the chi-squared statistic, also calculating the effect sizes of the differences. A discriminant analysis was then performed after the sample-splitting method according to context (winning and losing teams) in each of the 3 phases. It was found that the game-related statistics differentiate the winning from the losing teams in each phase of an international championship. The differentiating variables are both offensive and defensive, including action shots, sprints, goalkeeper-blocked shots, and goalkeeper-blocked action shots. However, the number of discriminatory variables decreases as the phase becomes more demanding and the teams become more equally matched. The discriminant analysis showed the game-related statistics to discriminate performance in all phases (preliminary, classificatory, and semifinal/bronze medal/gold medal phase) with high percentages (91, 90, and 73%, respectively). Again, the model selected both defensive and offensive variables.