The purpose of this study was to examine the effect of high-intensity physical activity during training on the biochemical status of thiamin and riboflavin in athletes. Thiamin and riboflavin concentrations in whole blood of a group of 19 athletes (6 men and 13 women) were measured during a low-intensity preparatory period and compared with measurements taken during a high-intensity training period. Additional variables measured included anthropometric characteristics, estimated energy expenditure during swim training, distance covered, resting energy expenditure obtained by indirect calorimetry, estimated energy requirement per day, and dietary intake of energy, thiamin, and riboflavin estimated from 3-day food records. For both male and female subjects, no major changes were observed in anthropometric characteristics or dietary intake, but energy expenditure during swim training per day significantly increased in the intensive-training period (496 ± 0 kcal in the preparation period compared with 995 ± 96 kcal in the intensive-training period for male subjects [p < .001] and 361 ± 27 kcal vs. 819 ± 48 kcal, respectively, for female subjects [p < .001]). Blood thiamin concentration decreased significantly during the intensive-training period compared with the preparation period (41 ± 6 ng/ml decreased to 36 ± 3 ng/ml for male subjects [p = .048], and 38 ± 10 ng/ml decreased to 31 ± 5 ng/ml for female subjects [p = .004]); however, the concentration of riboflavin was unchanged. These results suggest that intense training affects thiamin concentration, but not riboflavin concentration, in the whole blood of college swimmers.
Akiko Sato, Yoshimitsu Shimoyama, Tomoji Ishikawa and Nobuko Murayama
Rafael Gnat, Agata Dziewońska, Maciej Biały and Martyna Wieczorek
al., 2011 ; Hides, Stanton, McMahon, Sims, & Richardson, 2008 ), and this is in line with the initial subjective experiences of our participants. However, this potential influence was eliminated because, after the preexperimental training period, both IA and GA became equally familiar to the subjects
Karenina Arrais Guida Modesto, Pedro Ferreira Alves de Oliveira, Hellora Gonçalves Fonseca, Klaus Porto Azevedo, Vinicius Guzzoni, Martim Bottaro, Nicolas Babault and Joao Luiz Quagliotti Durigan
in isometric conditions. 16 , 19 Therefore, the hypothesis of the evaluation modality can be rejected. Nevertheless, the duration between the end of the training period and posttraining evaluation could influence the diverging results. Indeed, this period is generally not standardized and not
Diego Alonso-Fernandez, Yaiza Taboada-Iglesias, Tania García-Remeseiro and Águeda Gutiérrez-Sánchez
increase of 9.65% in the LG and 10.31% in the MG after the training period, there being disparity in the literature regarding this architectural variable. Thus, in a study on the vastus lateralis, Blazevich et al 15 obtained an increase of 11.0%, whereas Seynnes et al 28 obtained an increase of 7
Jarek Mäestu, Jaak Jürimäe, Kairi Kreegipuu and Toivo Jürimäe
The aims were to assess (a) the usefulness of RESTQ-Sport in the process of training monitoring and (b) whether a change in psychological parameters is reflected by similar changes in specific biochemical parameters. The high volume training period, in general, caused increases in stress scales and decreases in recovery scales of the RESTQ-Sport, while during recovery period, stress levels declined. Cortisol was not changed during the study period, but significant increases in creatine kinase activity were found during the high training period compared to reference period. The results of the present study demonstrate that changes in training volume were reflected by changes in the RESTQ-Sport scales. A close relationship was found between cortisol and creatine kinase activity and subjective ratings of stress and recovery.
Seong-won Han, Dae-yeon Lee, Dong-Sung Choi, Boram Han, Jin-Sun Kim and Hae-Dong Lee
This study aimed to examine whether muscle force and tendon stiffness in a muscle-tendon complex alter synchronously following 8-week whole-body vibration (WBV) training in older people. Forty older women aged 65 years and older were randomly assigned into control (CON, n = 15) and whole-body vibration (WBV) training groups (exposure time, n = 13; vibration intensity, n = 12). For the training groups, a 4-week detraining period was completed following the training period. Throughout the training/detraining period, force of the medial gastrocnemius (MG) muscle and stiffness of the Achilles tendon were assessed four times (0, 4, 8, and 12 weeks) using a combined system of dynamometer and ultrasonography. While muscle force gradually increased throughout the training period (p < .05), a significant increase in tendon stiffness was observed after 8 weeks (p < .05). These findings indicated that, during the early phase of WBV training, muscle force and tendon stiffness changed asynchronously, which might be a factor in possible musculotendinous injuries.
Riina A. Kekkonen, Tommi J. Vasankari, Timo Vuorimaa, Tari Haahtela, Ilkka Julkunen and Riitta Korpela
Heavy exercise is associated with an increased risk of upper respiratory tract infections. Strenuous exercise also causes gastrointestinal (GI) symptoms. In previous studies probiotics have reduced respiratory tract infections and GI symptoms in general populations including children, adults, and the elderly. These questions have not been studied in athletes before. The purpose of this study was to investigate the effect of probiotics on the number of healthy days, respiratory infections, and GI-symptom episodes in marathon runners in the summer. Marathon runners (N = 141) were recruited for a randomized, double-blind intervention study during which they received Lactobacillus rhamnosus GG (LGG) or placebo for a 3-mo training period. At the end of the training period the subjects took part in a marathon race, after which they were followed up for 2 wk. The mean number of healthy days was 79.0 in the LGG group and 73.4 in the placebo group (P = 0.82). There were no differences in the number of respiratory infections or GI-symptom episodes. The duration of GI-symptom episodes in the LGG group was 2.9 vs. 4.3 d in the placebo group during the training period (P = 0.35) and 1.0 vs. 2.3 d, respectively, during the 2 wk after the marathon (P = 0.046). LGG had no effect on the incidence of respiratory infections or GI-symptom episodes in marathon runners, but it seemed to shorten the duration of GI-symptom episodes.
Thomas Kyriazis, Gerasimos Terzis, Giorgos Karampatsos, Stavros Kavouras and Giorgos Georgiadis
The purpose of the current study was to investigate the relationship between fat-free mass and shot put performance at the beginning of the winter preparation cycle and at the first peak of the season (12 wk later) in well-trained shot-putters using the rotational style.
Eight national-level shot put athletes followed their individual training programs for a period of 12 wk aiming at the national indoor championship. Shot put performance with the rotational style as well as from the power position was determined before and after this 12 wk period. Body composition was determined before and after the training period with dual x-ray absorptiometry.
Shot put from the power position was increased by 3% (P = .03) while shot put with the rotational style was increased by 6.5% (P < .01). Fat-free mass, body fat and bone mineral density were not altered after the training period. The correlation coefficient between fat-free mass and shot put performance from the power position was significant (r = .76 preseason vs r = .66, competition; P < .05). The correlation coefficient between fat-free mass and shot put performance with the rotational style was significant at the beginning of the training period (r = .70, P < .05) but it was decreased to moderate and nonsignificant levels at competition (r = .55, ns).
These results suggest that the increase of fat-free mass might not be the most essential element for competition when the rotational shot put style is involved.
Erika Casolino, Cristina Cortis, Corrado Lupo, Salvatore Chiodo, Carlo Minganti and Laura Capranica
To anticipate outstanding athletic outcomes, the selection process of elite athletes simultaneously considers psychophysiological and technical parameters. This study aimed to investigate whether selected and nonselected athletes for the Italian national taekwondo team could be discriminated by means of sportspecific performances and psychophysiological responses to training.
5 established Italian national athletes and 20 elite Italian taekwondo black belt athletes (9 women, 16 men; age 23.0 ± 3.1 y; body mass 67.0 ± 12.1 kg).
To update the Italian national-team roster, the 20 elite athletes participated in a 1-wk selection camp (7 training sessions). Selected athletes (n = 10) joined established national athletes during the following 3-wk national training period (7 training sessions/wk). During the 1-wk selection camp, differences (P < .05) between selected and nonselected athletes in performances, heart-rate responses, blood lactate accumulation [La], subjective ratings of perceived exertion (session RPE), and mood were examined. During the 3-wk national training period, differences (P < .05) in mood between selected and established national athletes were investigated.
With respect to nonselected athletes, selected athletes responded better to training in terms of session RPE (P = .047) and [La] (P = .046). No difference in performance and mood between subgroups emerged. After the 3-wk national training period, differences (P = .035) emerged for confusion, with decreases in the established national athletes and increases for recently selected athletes.
Session RPE and [La] seem to be more effective than psychological measures in discriminating between elite taekwondo athletes. Evaluation of mood could be effective in monitoring athletes’ response to national training.
Ryland Morgans, Adam Owen, Dominic Doran, Barry Drust and James P. Morton
To monitor resting salivary secretory immunoglobulin A (SIgA) levels in international soccer players during the short-term training period that precedes international match play.
In a repeated-measure design, saliva samples were obtained from 13 outfield soccer players who participated in the training camps preceding 7 games (5 home and 2 away) of the 2014 FIFA World Cup qualifying campaign. Samples were obtained daily for 4 d preceding each game (and analyzed for SIgA using the IPRO oral-fluid-collection system) at match day minus 1 (MD-1), minus 2 (MD-2), minus 3 (MD-3), and minus 4 (MD-4).
SIgA displayed a progressive decline (P = .01) during the 4-d training period (MD-4, 365 ± 127 μg/mL; MD-3, 348 ± 154 μg/mL; MD-2, 290 ± 138 μg/mL; MD-1, 256 ± 90 μg/mL) such that MD-1 values were significantly lower (P = .01) than both MD-4 and MD-3. The 95% confidence intervals for the differences between MD-1 and MD-4 were –191 to –26 and between MD-1 and MD-3 were –155 to –28.
Data demonstrate that a short-term soccer-training camp in preparation for international competition induces detectable perturbations to mucosal immunity. Future studies should monitor SIgA (as a practical and noninvasive measure of immunity) alongside internal and external measures of training load in an attempt to strategically individualize training and nutritional strategies that may support optimal preparation for high-level competition.