Giovanni Melchiorri

Effect of different sports on body cell mass in highly trained athletes.

Abstract.The objective of this study was to verify the impact of various sports on body cell mass (BCM). Ninetyeight male subjects, 17–33 years of age, participated in the study. The sample included athletes from three professional Italian football (soccer) teams, representing three different divisions (A, n=16; B, n=14; and C, n=18), judo athletes (J, n=10), and water polo athletes (W, n=14) who all competed at the national level. Twenty-six age-matched individuals served as the control group (CG). Fat-free mass (FFM), fat mass (FM), percent body fat (%BF), and BCM were assessed using bioimpedance spectroscopy (BIS). There were no significant differences in body weight and FFM among the groups. A and B were significantly taller than J and CG. B had a significantly lower body mass index (BMI; kg/m2) than CG, while C had a significantly lower BMI than J and CG. CG had a significantly greater FM and %BF than A, B, and C. C had a significantly lower BCM than Aand B. CG had a significantly lower BCM than A, B, J, and W. In conclusion, differences in BCM exist among athletes of different sports, and among athletes within the same sport who compete at different levels.

Physical activity energy expenditure measured using a portable telemetric device in comparison with a mass spectrometer

Background: Several studies have evaluated the accuracy of portable metabolic gas analysis systems, which measure physical activity energy expenditure. Since the Cosmed K2 telemetric system, two K4 devices (RQ and b2) have been developed. Objective: To compare measurements using the Cosmed K4 RQ with measurements by a traditional method (mass spectrometer) for a sample of healthy subjects performing physical exercise of various intensities. Methods: Nine healthy male footballers (mean (SD) age 18.3 (2.2) years) performed an incremental exercise running test from 8 km/h to exhaustion, with an increase of 2 km/h for each level of the test protocol. The expired air was collected simultaneously using the Cosmed K4 RQ and Airspec QP9000 mass spectrometer. Oxygen consumption (Vo2) and carbon dioxide production (Vco2) were measured at rest and at each exercise intensity. Results: No significant differences were found between Vo2 and Vco2 measured by the two instruments, at rest or during exercise. Conclusions: The application of the Cosmed K4 RQ system for Vo2 and Vco2 measurements at rest and during both submaximal and maximal exercise may be of interest to sport physiologists, nutritionists, and doctors.

Game activity and blood lactate in men's elite water-polo players.

Melchiorri, G, Castagna, C, Sorge, R, and Bonifazi, M. Game activity and blood lactate in mens elite water-polo players. J Strength Cond Res 24(10): 2647-2651, 2010-The purpose of this study was to examine game demands during highly competitive mens water-polo games after the introduction of the new Federation International Natation Association (FINA) rules. Participants of this study were 77 outfield international level mens water-polo players (age 25.9 ± 4.5 years, height 188 ± 4.5 cm, body mass 93 ± 10.9 kg). Game earlobe blood lactate, speed, and distance covered (semiautomatic image recognition system) were measured during 6 highly competitive matches (FINA International Tournament). In the game, players covered 1,613 ± 150 m (n = 68). This corresponds to a mean coverage rate of 54 ± 5.8 m·min−1 (n = 68). At speeds faster than 1.4 m·s−1 (high-intensity swimming), players covered 44% of the total distance. A significant decrease in coverage rate was detected during the final stage of the game. Mean blood-lactate concentration was 7.7 ± 1.0 mmol·L−1 (range 2.2-14.3). Center Defenders (1,816 ± 496 m) covered significantly (p < 0.05) more distance swimming compared to Field (1,676 ± 348 m) and Center-Forward (1,317 ± 281 m) players. Mean match blood-lactate concentrations for Center Forwards, Center Defenders, and Field Players were 11.2 ± 1.0 (3-14.3), 6.7 ± 0.9 (1.4-8), and 5.3 ± 0.9 mmol·L−1 (2.2-11.9), respectively. This study confirmed the high-intensity nature of male elite level water polo showing remarkable role-dependent game demands. As a result, strength and conditioning interventions should be individualized and mainly address intermittent high-intensity endurance and anaerobic fitness.

Ambulatory assessment of shoulder abduction strength curve using a single wearable inertial sensor

The aim of the present article was to assess the reliability of strength curves as determined from tridimensional linear accelerations and angular velocities measured by a single inertial measurement unit (IMU) fixed on the upper arm during a shoulder abduction movement performed holding a 1 kg dumbbell in the hand. Within-subject repeatability of the task was assessed on 45 subjects performing four trials consisting of one maximal shoulder abduction-adduction movement. Intraclass correlation coefficient (ICC) was computed on the average movement angular velocity (VEL) and range of movement (ROM) across the four trials. Within-subject repeatability of torque curves was assessed in terms of waveform similarities by computing the coefficient of multiple determination (CMD). Accuracy of the estimated ROM was assessed using an isokinetic dynamometer. High ICC values of ROM (0.955) and VEL (0.970) indicated a high within-subject repeatability of the task. A high waveform similarity of torque curves was also found between trials (CMD = 0.867). Accuracy with respect to isokinetic dynamometer in estimating ROM was always <1 degree (p = 0.37). This study showed the effectiveness of using a single wearable IMU for the assessment of strength curve during isoinertial movements in a way that complies with the needs of clinicians in an ambulatory setting.

Modulation of synaptic plasticity by short-term aerobic exercise in adult mice

&NA; Physiological effects of different types, of continuous and interval aerobic training, have been largely described and studied in the adult man. It was previously indicated that interval training plays an important role in maximizing both peripheral muscle and central cardiorespiratory adaptations, permitting significant functional improvement even in healthy sedentary subjects. Since the outcome of different aerobic training trials on cognitive processes had never been evaluated, we compared, on an experimental mouse model, the effects of four training exercise protocols, named respectively C100, I100, C50 and I50 depending on the volume and on the type of training proposed, continuous or interval method. Therefore, to asses quantitative and qualitative functional changes, we analyzed several physical parameters before and after 6 weeks training in all four groups with respect to the control sedentary animals and we studied synaptic plasticity, by extracellular in vitro recordings, in hippocampal mouse slices, a region involved in learning and memory processes. We found that all four protocols of exercise applied in this study exerted positive effects on both physical and training parameters inducing weight augmentation, strength endurance and aerobic endurance increase, and potentiation of motor coordination. However, the improvement observed failed to induce an enhancement in synaptic plasticity in three out of four exercise protocols and only in the slices from mice trained with the interval 50% volume exercise the long term potentiation (LTP) increased with respect to the sedentary group. These findings suggest that motor activity exerts positive effects on cognitive processes provided that certain principles are respected, such as the training load and the elements of which it is composed, in order to plan the right quantitative and qualitative parameters and the appropriate recovery periods. HighlightsAerobic training induces strength endurance and aerobic endurance increase.Aerobic training promotes a potentiation of motor coordination.Enhancement in synaptic plasticity depends on the training protocol proposed.Motor acivity exerts positive effects on cognitive processes if the training load is adequate and appropriate recovery periods are respected.

Testing and training of the eggbeater kick movement in water polo: applicability of a new method

Abstract Melchiorri, G, Viero, V, Triossi, T, Tancredi, V, Galvani, C, and Bonifazi, M. Testing and training of the eggbeater kick movement in water polo: Applicability of a new method. J Strength Cond Res 29(10): 2758–2764, 2015—In water polo, many of the technical actions and the contacts with the opponent take place in quasi-vertical floating position using 2 types of lower limb actions: the eggbeater kick is used most often in fighting and passing and the breaststroke kick in jumping and throwing. The aim of this study was to identify a new system to evaluate and to train the eggbeater kick movement and to verify its applicability. Twenty amateur players and 22 elite players participated in the study. A jacket, homemade and easy to make, allowing the application of an overload submerged in water but not hindering breathing or mobility, was used. Standard anthropometry and a test consisting of different trials of the eggbeater kick action until exhaustion with an increasing overload (5, 7.5, 10, 12.5, 15, and 17.5 kg) were collected. Time to exhaustion and the overload estimated maximum value (OEMV) at second 2 were determined for each load. Body weight, height, and lower limb muscle performance of the elite and nonelite players were significantly different from each other (p ⩽ 0.05). The effectiveness of the different measured variables in both subgroups and that of the OEMV was evaluated with receiver operating characteristic (ROC) curve analysis. Areas under the ROC curve for the different overloads were 0.72 (0.53–0.92) for 5 kg, 0.80 (0.68–0.90) for 7.5 kg, 0.87 (0.77–0.91) for 10 kg, and 0.88 (0.84–0.92) for 12.5 kg overload. Our results show that the test is sensitive enough and therefore can be used to plan and control training and injury recovery.

New approach to evaluate late arm impairment and effects of dragon boat activity in breast cancer survivors

Abstract To verify the applicability of a new approach based on the strength curves (SCs) methodology in late arm impairment in breast cancer (BC) survivors and to evaluate the effects of dragon boat (DB) activity on the late regaining of the muscle strength, upper limb impairment, and quality of life in patients undergoing surgery for BC. Retrospective observational study on 64 subjects (54.5 ± 9.7 years), 47 of them had undergone unilateral mastectomy surgery and were evaluated for late arm impairment. A clinical evaluation of the shoulder and compilation of functional assessment (DASH, Rowe, Constant–Murley) and quality of life (SF-36) scales were carried out. Assessment of muscle strength with SC obtained with isometric assessments and serratus anterior muscle test were performed. Differences between the SC are evident between healthy and operated subjects. Among the 3 groups of operated subjects the difference in strength is maximum at 0°. Statistically significant difference was found between operated and nonoperated only in SF-36 scale. No significant difference was found between groups for shoulder instability and winged scapula. The SC can be used in the study of upper limb impairment after surgery for BC: measurements carried out at 1st degrees of the range of motion are more useful for clinicians. DB activity is useful to reduce the late arm impairment.

Shuttle swimming test in young water polo players: reliability, responsiveness and age related value

BACKGROUND This study investigated the applicability of a sport-specific test, the Shuttle Swim Test, in young water polo players to measure RSA. The aims were: to assess the reliability and to measure the responsiveness of the SST in young water polo athletes, and to provide age-related values of SST. METHODS Three hundred thirty-three elite athletes (18.3±5.1 years) were involved in the study. Of these, 99 were young people under 13 (13.1±0.5 years) who also underwent measurements for reliability and responsiveness of the SST The following six measures was used to assess anthropometric characteristics of the sample: height, weight, chest circumference, hip circumference, waist circumference, and arm span. Two performance measures were performed on dry land: push up and chin up. RESULTS Reliability and responsiveness were measured by comparing the average speed of two trials: SST1 was 1.48±0.13 m·s-1 and SST2 1.47±.12 m·s-1. The SST showed good reliability in younger athletes (r=0.96). The Minimal Detectable Change is 0.06 m·s-1 (6 seconds of the total time) which corresponds to 3.6% of the average value measured, confirming the good responsiveness of the test. CONCLUSIONS Coaches and researchers can use this value in the interpretation of the SST test results: changes below these values could be related to a measurement error. The various age-related values reported may help technicians to better interpret the performance of their athletes during competition.

Anthropometric and performance measures to study talent detection in youth volleyball

BACKGROUND The aim of this work was to study anthropometric and performance measurements in 60 young male volleyball players (YV) and 60 youth not active in the sport (YNA) to assess which of these would be more useful to study the characteristics of potential performers. METHODS Eight measures to assess anthropometric characteristics, six performance measures and two tests for joint mobility were used. Also relative age and level of maturation were assessed. RESULTS The anthropometric variables, relative age and level of maturation measured did not show statistically significant differences between groups. The YV and YNA groups showed differences in the performance measures. YV group was characterized by a better performance of the ability to repeat short sprints, of the upper limbs, abdominal muscles and lower limbs, with a medium effect size (Shuttle Running Test: 0.6; Push-Up: 0.5; Sit-Up: 0.4; counter movement jump: 0.4). These performance variables were very sensitive and specific: the SRT measurement had the best positive likelihood ratio that indicates the utility of the test in identifying type of players (YV and YNA). CONCLUSIONS In talent detection in youth volleyball, in the 11-13 age range, performance variables should be preferred to anthropometric ones.