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Biomedical subjects

F Figura

Publications and source records attributed to F Figura.

17 recordsLinked to original sources
PubMed1995

Decrease of endurance performance during Olympic Triathlon.

The present study was carried out in order to quantify the athlete's endurance impairment after two out of three sequential events of Olympic Triathlon (OT). Furthermore the significance of ventilatory threshold (Tvent) and peak of oxygen uptake (VO2peak) as triathlete's performance predictors was assessed. Tvent and VO2peak were measured in six male triathletes performing an incremental treadmill test a week before an ad hoc triathlon event. The same test was applied immediately after the first two segments of the triathlon (1.5 km swim, 32 km bike). VO2peak and Tvent measured during the latter test were reduced compared to the first test. VO2peak decreased from 69 to 64 ml.kg-1.min-1 and Tvent from 58 to 51 ml.kg-1.min-1 p < 0.01), respectively. VO2peak and Tvent measured in the first test were well correlated (P < 0.05) to both running and cycling times. The Tvent measured during the second test was related to the running time but with a higher significance (p < 0.01) than in the first test. The impairment in the endurance performance induced by the first two segments of OT is an important aspect to consider both in training and in race strategy. These results also provide evidence that VO2peak and Tvent are good predictors of triathlon performance at least in cycling and running events.

Adult↗
PubMed1993

Heart rate, alveolar gases and blood lactate during synchronized swimming.

Heart rate, alveolar gas partial pressures and blood lactate (BLa) concentration were measured during synchronized swimming in six subjects. During upside-down breath-holding lasting 50 s, heart rate fell progressively from 98 +/- 14 to 70 +/- 7 beats min-1 (mean +/- S.D.). While breath-holding during the compulsory figures, the subjects' heart rate increased to 142 +/- 5 beats min-1 and then fell to 72 +/- 10 beats min-1. At the end of breath-holding, alveolar oxygen pressure had fallen significantly (60 mmHg), whereas alveolar carbon dioxide pressure showed only minor changes (48 mmHg). The increase in BLa concentration due to the execution of compulsory figures was approximately 1 mM; in the free routines, BLa concentration increased by 3.4 +/- 0.5 mM. The net energy cost of completing a compulsory figures lasting 45 s was 34.6 kJ.

Adolescent↗
PubMed1992

Force and power of preferred and non-preferred leg in young soccer players.

The purpose of this study was to assess the effects of soccer training on strength and power of leg extensor muscles in preadolescent boys and their possible influence in developing a muscular lateral dominance. Twenty male children (mean age 9.6 yr), ten soccer players and ten untrained subjects, participated in this study. Force and power were measured at five constant cranking velocities on an isokinetic bicycle dinamometer. Each isokinetic load was given after each trial. Force and power outputs were calculated for each limb. Soccer players always showed higher and statistically significant differences (p < 0.05) for force and power values for all considered pedal frequencies. No significant differences were observed for force and power values between preferred and non preferred limb. The results demonstrate the effect of soccer training on the increase of force and power of both legs regardless of lateral dominance.

Biomechanical Phenomena↗
PubMed1991

Prediction of ramp traversability for wheelchair dependent individuals.

The purpose of this research was to obtain a single objective criterion that would constitute a reliable prediction of length and grade limits for ramps that can be traversed by any special category of wheelchair dependent individuals (WDI). The maximal voluntary force (MVC) is the main limiting factor of the performance of WDI, thus the force required to traverse a ramp has been established by means of a simple mechanical model. The real time course of force application during ascent was experimentally obtained. Then, a simplified law of force application was introduced in a computer simulation program of kinetics and kinematics of ascent. Inputs to the model were also the mass of the subject plus wheelchair, the initial velocity of the chair, and the ramp length. The output of the program was the force requirement for any given length/grade. When capsizing conditions were encountered the simulation ended. We tested the results thus obtained having some selected WDI successfully traversing ramps with the predicted length/grade specifications.

Architectural Accessibility↗
PubMed1991

Assessment of static balance in children.

The ability in maintaining body balance of 6-, 8-, and 10-year-old children performing three balance tests on a force platform was studied. Thirty adult subjects served as a reference group. The mean radius (MR) of the posturogram and the mean speed (MS) of the center of foot pressure (COP) were used as the measuring parameters. Data were analyzed using two-way ANOVA, the Sheffe test and the Student "t" test with a .05 level of significance. A decrease with age in both mean radius and mean speed, indicating an increase in balance ability, was noted. A significant age main effect was found on all tests while significant gender main effect occurred only on the Tandem test. No significant age/sex interaction was found. Significant differences between the 10-year-old and adult groups occurred only in the more difficult balance tests.

Biomechanical Phenomena↗
PubMed1985

Lumbar spine loading during half-squat exercises.

Evaluation of the compressive load acting on the lumbar spine (L3-L4) during half-squat exercises executed with a barbell resting on the subject's shoulders was undertaken. The kinematics of the upper body segments of two male and two female subjects as well as the barbell were described using data obtained by means of an optoelectronic system (CoSTEL). L3-L4 compressive load was calculated using a model of the anatomy of the trunk musculoskeletal system. Filtered surface electromyographic trunk flexor recordings from the obliquus externus and rectus abdominis and trunk extensor erectores spinae muscles as well as measurement of the ground reaction forces were also carried out for predicted result validation. During half-squat exercises with barbell loads in the range 0.8 to 1.6 times body weight the compressive loads on the L3-L4 segment vary between 6 and 10 times body weight. Erectores spinae contraction force was predicted to be between 30 and 50% of the relevant maximal isometric force. The magnitude of trunk flexion was found to be the variable which influenced most spinal compression load.

Adult↗
PubMed1982

Angular displacements in the upper body of AK amputees during level walking.

The angular displacements of the longitudinal axis of the trunk, and of the latero-lateral axes of pelvis and shoulder girdle were measured in five normal subjects and four AK amputees during level walking at different speeds. Amputees used single axis prostheses with the SACH foot. Spatial measurements were carried out in three dimensions by means of a photogrammetric technique. The time functions of the target angles underwent harmonic analysis. Based on the Fourier coefficients, comparison was made between normal subjects' and amputees' angular displacements. Relevant findings permitted the identification of compensatory mechanisms adopted by amputees at trunk level as well as the assessment of the relationship between these latter mechanisms and those put into action at lower limb level.

Amputation, Surgical↗
PubMed1981

Biomechanics of sit-up exercises.

Sit-up exercises performed by four male subjects revealed the presence of initial lumbar "hollowing" (lumbar curvature), or trunk hyperextension, or both prior to trunk flexion. Maximum muscular moment developed at the hip joint, which varied with sit-up exercise, was of moderate order of magnitude. Intraesophageal pressure, cardiopulmonary response, and metabolic response to a commonly used sit-up exercise (curl-up) reveals it to be a light exercise which stresses the muscles of the lower limbs as well as those of the trunk, especially the abdominal muscle group.

Abdominal Muscles↗