José Antonio González-Jurado

Relationships between rating-of-perceived-exertion- and heart-rate-derived internal training load in professional soccer players: a comparison of on-field integrated training sessions.

PURPOSE To describe the internal training load (ITL) of common training sessions performed during a typical week and to determine the relationships between different indicators of ITL commonly employed in professional football (soccer). METHODS Session-rating-of-perceived-exertion TL (sRPE-TL) and heart-rate- (HR) derived measurements of ITL as Edwards TL and Stagno training impulses (TRIMPMOD) were used in 9 players during 3 periods of the season. The relationships between them were analyzed in different training sessions during a typical week: skill drills/circuit training + small-sided games (SCT+SSGs), ball-possession games+technical-tactical exercises (BPG+TTE), tactical training (TT), and prematch activation (PMa). RESULTS HR values obtained during SCT+SSGs and BPG+TTE were substantially greater than those in the other 2 sessions, all the ITL markers and session duration were substantially greater in SCT+SSGs than in any other session, and all ITL measures in BPG+TTE were substantially greater than in TT and PMa sessions. Large relationships were found between HR>80% HRmax and HR>90% HRmax vs sRPE-TL during BPG+TTE and TT sessions (r=.61-.68). Very large relationships were found between Edwards TL and sRPE-TL and between TRIMPMOD and sRPE-TL in sessions with BPG+TTE and TT (r=.73-.87). Correlations between the different HR-based methods were always extremely large (r=.92-.98), and unclear correlations were observed for other relationships between variables. CONCLUSION sRPE-TL provided variable-magnitude within-individual correlations with HR-derived measures of training intensity and load during different types of training sessions typically performed during a week in professional soccer. Caution should be applied when using RPE- or HR-derived measures of exercise intensity/load in soccer training interchangeably.

Comparison of the effect of repeated-sprint training combined with two different methods of strength training on young soccer players.

Abstract Campos-Vazquez, MA, Boza, SR, Toscano-Bendala, FJ, Leon-Prados, JA, Suarez-Arrones, L, and Gonzalez-Jurado, JA. Comparison of the effect of repeated-sprint training combined with two different methods of strength training on young soccer players. J Strength Cond Res 29(3): 744–751, 2015—The aim of this study was to assess the effect of combining repeated-sprint training with 2 different methods of muscle strength training on physical performance variables in young players. Twenty-one soccer players with mean (±SD) age of 18.1 (±0.8) years, weight 69.9 (±6.5) kg, and height 177.1 (±5.7) cm, and competing in U-19 category, were randomly assigned to 2 experimental groups: squat group (SG: n = 10) and take-off group (TG: n = 11). Intervention in both groups consisted of the combination of a weekly session of repeated-sprint training (the same for both groups), with 2 weekly sessions of strength training (different for each group), for 8 weeks in the final period of the season. The strength sessions for the SG consisted of conducting a series of full squats executed at maximum velocity in the concentric phase. Intervention in the TG was the performance of 2 specific strength exercises (take-offs and change of direction), with measurements taken before and after consideration of the following variables: repeated-sprint ability (RSA), yo-yo intermittent recovery test level 1 (YYIRT1), countermovement jump (CMJ), and average velocity in full squat progressive loads test. The SG improved CMJ height in 5.28% (p ⩽ 0.05) and FS37.5-47.5-67.5 (p ⩽ 0.05), whereas the TG improved FS17.5-27.5-37.5-47.5-67.5 (p ⩽ 0.05). There were no significant changes in the values of RSA or YYIRT1 in either group. The results seem to show that the combination of a weekly session of repeated-sprint training with 2 weekly sessions of strength training could be an insufficient stimulus to improve RSA in the final period of the season.

Efecto del Phlebodium Decumanum sobre los cambios en niveles plasmáticos de testosterona y cortisol inducidos por el ejercicio en sujetos no entrenados

Background: Phlebodium Decumanum is a type of fern that could have an immune or stress response modulating action. Aim: To evaluate if the consumption of a preparation obtained from Phlebodium Decumanum, modifies the changes induced by exercise in plasma levels of testosterone and cortisol. Material and methods: Fourteen male subjects aged 22 ± 2 years were randomized to consume Phlebodium Decumanum and 10 subjects, aged 23 ± 1 years were ascribed to consume a placebo. Both groups performed a standard exercise program, three times a week during one month. Plasma free testosterone and cortisol levels were measured before and 48 hours after the last session of the exercise program. Results: Cortisol levels increased significantly from 18.9 ± 6.8 to 26.2 ± 5.9 ∝g/dl, in the control group. In the group consuming the study product, no changes were detected (20.0 ± 4.6 and 20.9 ± 5.9) ∝g/dl before and after the exercise program, respectively). Plasma free testosterone decreased significantly in both groups from 36.1 ± 11.04 to 20.7 ± 4.3 pg/ml in the control group and from 33.7 ± 10.0 pg/ml to 18.6 ± 4.9 pg/ml in study group. Conclusions: The cortisol levels increased significantly in the control group but not in the study group. Therefore we can suggest that consumption of Phlebodium Decumanum would be able to modulate the response of this hormone to physical stress (Rev Med Chile 2009; 137: 497-503). (Key words: Excercise tests; Ferns; Hydrocortisone)

Efectos del ejercicio físico sobre la cognición en mujeres tratadas con lovastatina

INTRODUCTION The deterioration of cognition is highly predominant in older adults. OBJECTIVE The aim of this study was to analyze the effects of a walking program on the cognition and blood concentration of lipids in women over 60 years of age who were being treated with lovastatin. MATERIALS AND METHODS Participants were distributed in two groups: An exercise group (EG, n=45) with aerobic training and an inactive sedentary group (SG, n=22). The cognitive state of the subjects was assessed through the Spanish Mini-Cog Test version of the MMSE; lipoproteins were quantified using a lipid profile test, and the cardiorespiratory fitness was measured using the six-minute walking test (6MWT). RESULTS EG showed a significant increase (p<0.05) in cardiorespiratory fitness and in HDL-C concentrations. Furthermore, the results from the cognition tests showed a large effect size in spatial orientation and in and calculation. The decrease in LDL-C was not significant (p>0.05). CONCLUSION A controlled and progressive walking program for older women treated with Lovastatin may induce a boost of brain activity linked to HDL-C, which could delay cognitive impairment.

Effects of Muscle Fatigue Induced by Countermovement Jumps on Efficacy Parameters of Instep Ball Kicking in Soccer

The purpose was to study the effects of muscle fatigue induced by countermovement jumps (CMJ) on instep kick foot velocity in young male soccer players. Fifteen under-18 soccer players from a professional club performed maximal velocity instep kicks before and after a fatigue protocol that consisted of continuous CMJ. Foot velocity at impact without fatigue, foot velocity at impact with fatigue, CMJ height without fatigue, maximum jump height in fatigue test, and CMJ height change in fatigue test on a dynamometric platform were measured. There was a significant difference between jump height with and without fatigue (P = .00; ES = 0.8), but there were no significant differences between kicking with fatigue and without fatigue (P = .580, ES = 0.10). In conclusion, although the protocol was intense enough to generate fatigue in the muscles involved in CMJ, there were no significant differences in kicking velocity under fatigue conditions with respect to kicking without fatigue in the soccer players studied.

Composición corporal y condición física de escolares colombianos de educación secundaria y media de Ibagué

INTRODUCTION Body composition and other components of physical fitness have proved to be important markers of health condition. OBJECTIVE To analyze body composition and physical fitness in Colombian students from public high schools of Ibagué, as well as to study differences between sexes and age groups, and establish correlations between some of the variables. MATERIALS AND METHODS The sample consisted of 1,253 students (601 males; 652 females), with an age range of 10-20 years. The ALPHA-Fitness test (extended version) was applied. Body Mass Index (BMI), waist circumference and fat percentage were assessed. RESULTS Differences between sexes were found in the variables studied, with greater BMI and fat percentage among females (20.6 kg/m2 vs. 19.4 kg/m2 and 26.1% vs. 16.8%, respectively); however, waist circumference was greater in males (69.6 cm vs. 67.9 cm), who also showed better fitness in the rest of the physical tests (p<0.05). In both sexes, age was associated to increases in BMI (p<0.05), and among females to fat percentage as well (p<0.05); among males it was the opposite, as in them, age was inversely associated to fat percentage (p<0.05). For the rest of the physical tests, age was positively associated to fitness both in men and women, except for maximal oxygen uptake (VO2 max). Correlations were found between some of the variables studied. CONCLUSIONS Adiposity was significantly greater in females than in males (p<0.05). Males showed better levels of aerobic, musculoskeletal and motor capacities.