Aldo M. Costa

Effects of high-speed power training on functional capacity and muscle performance in older women.

The purpose of the study was to examine the effects of 12 weeks high-speed power training on isometric contraction (handgrip strength), maximal strength (1RM), muscle power (walking velocity, counter movement jump and ball throwing) and functional tasks of the arm and leg muscles (sit-to-stand and get-up and go). Fifty-six older women were divided into an experimental group and a control group [EG, n=28, 62.5 (5.4) years; CG: n=28, 62.5 (4.3) years]. The EG was submitted to a high-speed power training that consisted of 40% of one repetition maximum (1<RM) to 75% of 1RM); 3 sets 4-12 reps, countermovement jump and medicine ball (1.5 kg) throwing. Over the 12-week training period, the EG significantly increased dynamic and isometric strength performance (57% to 61%), muscle power (range from 14% to 40%) (P<0.05) and function (P<0.05). No significant magnitudes of increase were observed in the CG. These data indicate that high-speed power training is an effective exercise approach leading to large gains in upper and lower extremity muscle performance and function capacity.

Genetic Inheritance Effects on Endurance and Muscle Strength

Top-level sport seems to play a natural Darwinian stage. The most outstanding athletes appear to emerge as a result of exogenous influences of nature and/or coincidence, namely, the contingency of practicing certain sport for which their talents best fit. This coincidence arises because certain individuals possess anatomical, metabolic, functional and behavioural characteristics that are precisely those required to excel in a given sport. Apart from the effects of training, there is strong evidence of genetic influence upon athletic performance. This article reviews the current state of knowledge regarding heritable genetic effects upon endurance and muscle strength, as reported by several twin and family studies. Due, probably, to the inaccuracy of the measurement procedures and sampling error, heritability estimates differ widely between studies. Even so, the genetic inheritence effects seem incontrovertible in most physical traits: ~40–70% for peak oxygen uptake and cardiac mass and structure, and ~30–90% for anaerobic power and capacity, ranging according to the metabolic category. Studies in development by several researchers at this present time seem to guarantee that future reviews will include twins and family studies concerning genes associated with the adaptive processes against hormetic agents, such as exercise, heat and oxidative stress.

The effects of concurrent resistance and endurance training follow a detraining period in elementary school students.

Abstract Santos, AP, Marinho, DA, Costa, AM, Izquierdo, M, and Marques, MC. The effects of concurrent resistance and endurance training follow a detraining period in elementary school students. J Strength Cond Res 26(6): 1708–1716, 2012—The purpose of this study was to compare the effects of an 8-week training period of resistance training alone (GR), or combined resistance and endurance training (GCOM), followed by 12 weeks of detraining (DT) on body composition, explosive strength, and V[Combining Dot Above]O2max adaptations in a large sample of adolescent school boys. Forty-two healthy boys recruited from a Portuguese public high school (age: 13.3 ± 1.04 years) were assigned to 2 experimental groups to train twice a week for 8 weeks: GR (n = 15), GCOM (n = 15), and a control group (GC: n = 12; no training program). Significant training-induced differences were observed in 1- and 3-kg medicine ball throw gains (GR: +10.3 and +9.8%, respectively; GCOM: +14.4 and +7%, respectively), whereas no significant changes were observed after a DT period in both the experimental groups. Significant training-induced gains in the height and length of the countermovement (vertical-and-horizontal) jumps were observed in both the experimental groups. No differences were perceived after a DT period in lower limb power. Time at 20 m decreased significantly for both intervention programs (GR: −11.5% and GCOM: −12,4%, <0.00), but either GR or GCOM groups kept the running speed after a DT period of 12 weeks. After training, the V[Combining Dot Above]O2max increased only significantly for GCOM (4.6%, p = 0.01). A significant loss was observed after a DT period in GR but not in GCOM. Performing resistance and endurance training in the same workout does not impair strength development in young school boys. As expected, strength training by itself does not improve aerobic capacity. Our results also suggest that training program effects even persist at the end of the DT period.

Muscle performance and functional capacity retention in older women after high-speed power training cessation.

Power declines more steeply than strength with advancing age and training cessation among older women and is associated with the loss of functional ability. We tested the hypothesis that the impact of 6 weeks of detraining (DT) subsequent to 12 weeks of high-speed power training on maximal strength (1RM) of the arm and leg muscles, power performance (counter movement jump and ball throwing) and functional task (sit-to-stand test) would decrease physical performance, and specifically power performance. Thirty-seven older women were divided into an experimental group and a control group [EG, n=20, 65.8 (2.5) years; CG: n=17, 64.8 (2.8) years]. Muscular strength, power and functional testings were conducted before the initiation of training (T1), after 12 weeks (T2) and after 6 weeks of DT (T3). During the 12 weeks of training, EG significantly increased their dynamic strength performance (range from 41.9 to 64.1%), muscle power output (range from 18.2 to 33.6%) (p<0.05) and function (15.8%) (p<0.05). No significant differences were observed in the magnitude of the increases in CG. Short-term DT led to larger effects on maximal strength (18.1-23.8%) (p<0.05) of both upper and lower extremity muscles than in muscle power (2-4.5%) and function (2.8%) (p<0.05). However, all measurements remained higher (12.6-36.4%; p<0.05) than in pre-training levels. These data indicated that DT may induce larger declines in muscle strength than in power output and preserved physical independence, mediated in part, by the effectiveness of high-speed power training particularly developed for older women.

Relationships Between Vertical Jump Strength Metrics and 5 Meters Sprint Time

Relationships Between Vertical Jump Strength Metrics and 5 Meters Sprint Time The aim of this study was to examine the relationship between short sprint time (5 m) and strength metrics of the countermovement jump (CMJ) using a linear transducer in a group of trained athletes. Twenty-five male, trained subjects volunteered to participate in the study. Each volunteer performed 3 maximal CMJ trials on a Smith machine. Peak instantaneous power was calculated by the product of velocity taken with the linear transducer. For sprint testing, each subject performed three maximum 5 m sprints. Only the best attempt was considered in both tests. Pearson product-moment correlation coefficients between 5 m sprint performance and strength metrics of the CMJ were generally positive and of clear moderate to strong magnitude (r = -0.664 to -0.801). More noticeable was the significant predictive value of bar displacement time (r= ~0.70) to sprint performance. Nevertheless, a non-significant predictive value of peak bar velocity and rate of force development measurements was found. These results underline the important relationship between 5 m sprint and maximal lower body strength, as assessed by the force, power and bar velocity displacement. It is suggested that sprinting time performance would benefit from training regimens aimed to improve these performance qualities.

The relative age effect among elite youth competitive swimmers

Abstract The aim of this study was to analyse the relative age effect (RAE) in competitive swimming. The best 50 Portuguese swimmers (12- to 18-year-olds) for the main individual swimming pool events of both genders were considered. Analysis was conducted on 7813 swimming event participants, taking account of respective swimmer birth dates and the Fédération Internationale de Natation points gained. Differences in the distribution of birth dates by quarter year were determined using the Chi-square. A one-way analysis of variance ANOVA was used to test for differences measured in points between individuals by quarterly birth year intervals. A two-way analysis of variance ANOVA was also conducted to test the interaction between gender and seasonal birth date with regard to performance. The results show an inequitable distribution (p<0.01) of birth dates by quarter for almost all age groups and both genders. However, the distribution of birth dates by quarter for each considered swim event shows that RAE seems to exist only for 12-year-old females and 12- to 15-year-old males. Analysing mean swimming performance, post-hoc results (p<0.01) show no consistency in RAE. Higher performance occurs among older swimmers only in 100 m butterfly (female 1998, 1st≠2nd quarter, p=0.003). The results also show no interaction between gender and seasonal birth date (p<0.01). Findings of this study show that a higher number of swimmers, particular males, are born in the first two quarters of the year, although there is mostly no effect of seasonal birth date on performance differences within the top 50 swimmers.

High level swimming performance and its relation to non-specific parameters: a cross-sectional study on maximum handgrip isometric strength.

The relationship between handgrip isometric strength and swimming performance was assessed in the four competitive swimming strokes in swimmers of different age groups and of both sexes. 78 national-level Portuguese swimmers (39 males, 39 females) were selected for this study. Grip strength, previously used as a marker of overall strength to predict future swimming performance, was measured using a hand dynamometer. The best competitive time at 100 and 200 m in all four swimming strokes were converted into 2010 FINA points. Non-parametric tests were used to evaluate differences between groups. Pearson product-moment correlations were computed to verify the association between variables. Handgrip maximum isometric strength was significantly correlated with swimming performance, particularly among female swimmers. Among female age group swimmers, the relationship between handgrip and 100-m freestyle was significant. Handgrip isometric strength seems to be related to swimming performance, especially to 100-m freestyle and in female swimmers. For all other distances and strokes, technique and training probably are more influential than semi-hereditary strength markers such as grip strength.

The Effects of Concurrent Resistance and Endurance Training Follow a Specific Detraining Cycle in Young School Girls

The Effects of Concurrent Resistance and Endurance Training Follow a Specific Detraining Cycle in Young School Girls The purpose of this study was to compare the effects of an 8-week training period of strength training alone (GR), or combined strength and endurance training (GCOM), followed by 12-weeks of de-training (DT) on body composition, power strength and VO2max adaptations in a schooled group of adolescent girls. Methods: Sixty-seven healthy girls recruited from a Portuguese public high school (age: 13.5±1.03 years, from 7th and 9th grade) were divided into three experimental groups to train twice a week for 8 wks: GR (n=21), GCOM (n=25) and a control group (GC: n=21; no training program). Anthropometric parameters variables as well as performance variables (strength and aerobic fitness) were assessed. Results: No significant training-induced differences were observed in 1kg and 3kg medicine ball throw gains (2.7 to 10.8%) between GR and GCOM groups, whereas no significant changes were observed after a DT period in any of the experimental groups. Significant training-induced gains in CMVJ (8 to 12%) and CMSLJ (0.8 to 5.4%) were observed in the experimental groups. Time of 20m significantly decreased (GR: -11.5% and GCOM: -10%) after both treatment periods, whereas only the GR group kept the running speed after a DT period of 12 weeks. After training VO2max increased only slightly for GCOM (4.0%). No significant changes were observed after the DT period in all groups, except to GCOM in CMVJ and CMSLJ. Conclusion: Performing simultaneous strength and endurance training in the same workout does not appear to negatively influence power strength and aerobic fitness development in adolescent girls. Indeed, concurrent strength and endurance training seems to be an effective, well-rounded exercise program that can be prescribed as a means to improve initial or general strength in healthy school girls. De-training period was not sufficient to reduce the overall training effects.

Effects of Two Different Training Programs with Same Workload on Throwing Velocity by Experienced Water Polo Players

To investigate the effects of two different strength-training programs with the same workload (impulse) on throwing velocity in water polo, 30 water polo players (M age = 17.1 yr., SD = 4.9; M mass = 71.2 kg, SD = 14.7; M height =1.75 m, SD = 0.09 m) were randomly divided in two groups based upon throwing performance with water polo ball. The medicine-ball training group performed 3 × 6 reps with a 3-kg medicine ball, while the combination training group completed 1 × 9 repetitions with the 3-kg medicine ball, followed by 3 × 14 repetitions with a water polo ball. Both groups trained eight weeks twice per week in addition to their regular water polo training. Throwing velocity was measured with a Doppler radar gun before and after the training period. Testing included throws with a water polo ball on land and in water, as well as with 1-kg and 3-kg medicine balls on land. Statistically significant increases were found in mean peak throwing velocity with the water polo, 1-kg, and 3-kg medicine balls after training. No differences between the groups were found, except in throwing velocity with water polo on land, with a statistically significantly larger increase for the combination training group (+ 7.6%) than the medicine-ball training group (+ 3.4%). These findings indicate that after training with the same workload (impulse), increases in throwing velocity in water polo are similar and suggesting workload may be a critical variable for training results.

Training strategy of explosive strength in young female volleyball players.

OBJECTIVE The aim of this study was to examine the effect of an 8-week combined jump and ball throwing training program in the performance of upper and lower extremities among young female volleyball players of the high school. MATERIALS AND METHODS A total of 20 young female volleyball players playing at Scholar Sport in High School at the district level were divided in two groups: the experimental group (n=10; 14.0±0.0 years; 1.6±0.1 m; 52.0±7.0 kg and 20.7±2.4% body mass) and the control group (n=10; 13.8±0.4 years, 1.6±0.1 m; 53.5±4.7 kg and 20.3±1.7% body mass). The experimental group received additional plyometric and ball throwing exercises besides their normal volleyball practice. The control group underwent only their regular session of training. RESULTS Strength performance in the experimental group significantly improved (medicine ball and volleyball ball throwing: P=0.00; and counter movement jump: P=0.05), with the improvement ranging from 5.3% to 20.1%. No significant changes in strength performance were observed in the control group (P>0.05). CONCLUSIONS The 8-week combined jump and ball throwing training can significantly improve muscular performance in young female volleyball players. These findings may be useful for all physical education teachers and volleyball coaches.