Effects of Carbohydrate Mouth Rinsing on Salivary Lysozyme, Mood States and Running Performance Among Recreational Runners

Introduction

Carbohydrate (CHO) mouth rinsing can enhance sports performance through a central action mediated by receptors in the mouth. This study examined the effect of a CHO mouth rinse on salivary lysozyme concentrations, mood states and running performances.

Methods

Ten males recreational runners were randomised to three running trials with a 1 week recovery period between the trials. Each trial involved running at 75% maximum heart rate (HRmax) for 1 h, followed by a 15 min time trial. The participants used a CHO mouth rinse, placebo (PLA) solution or control (CON, no solution) every 15 min during the exercise. Heart rate (HR), rating of perceived exertion (RPE) and mood states were recorded pre-, during and post-exercise. Saliva samples were collected pre-, post- and 1 h post-exercise.

Results

There was no significant interaction and time effect (P > 0.05) on the salivary lysozyme concentration and running performance, but it was significant (P < 0.05) for HR and RPE (increase in all trials). However, there was no significant difference (P > 0.05) in salivary lysozyme concentrations, running performances, HR values or RPE between the trials. Mood states were not significantly different (P > 0.05) between the trials, but one of the mood sub-scales showed a significant (P < 0.001) time effect (increase fatigue in all trials).

Conclusion

CHO mouth rinsing did not affect physiological parameters, salivary lysozyme concentrations, mood states or running performance among recreational runners.

Confirmatory Factor Analysis of the Malay-Language Transtheoretical Model of Physical Activity among Malaysian Primary School Children

Introduction

The transtheoretical model (TTM) is an integrative model of intentional change consisting of stages of change, processes of change, decisional balance and self-efficacy. This study aimed at validating the TTM questionnaires on physical activity for Malaysian children using confirmatory factor analysis.

Methods

The participants were 381 Malay students (188 male; 193 female), aged 10–12 years old, with a mean age of 10.94 (SD = 0.81). The original version of the TTM was translated into the Malay language using forward and backward translation. Certain phrases were adapted based on the local culture and vocabulary suitable for primary school students.

Results

The final measurement models and their fit indices were: processes of change (CFI = 0.939, TLI = 0.925, SRMR = 0.040, RMSEA = 0.030); decisional balance (CFI = 0.897, TLI = 0.864, SRMR = 0.045, RMSEA = 0.038); and self-efficacy (CFI = 0.934, TLI = 0.915, SRMR = 0.042, RMSEA = 0.032).

Conclusion

Care must be taken when using the TTM with children, as it has been prevalently validated with adults. The final version of the TTM questionnaire for Malay primary school children had 24 items for process of changes, 13 items for self-efficacy and 10 items for decisional balance.

The Effects of Brain Breaks on Motives of Participation in Physical Activity among Primary School Children in Malaysia

Brain breaks is a physical activity (PA) video designed for school settings that is used to stimulate student's health and learning. The purpose of this study is to measure the effects of brain breaks on motives of participation in PA among primary school children in Malaysia. Purposive sampling was used to divide 159 male and 176 female students aged 10 to 11 years old, mean (standard deviation (SD)) = 10.51 (0.50), from two schools in Kelantan, Malaysia into intervention (n = 183) and control (n = 152) groups. Students undertook brain breaks activities on school days (five minutes per session) spread out for a period of four months. Mixed factorial analysis of variance (ANOVA) was used to test the students' motives of participation in PA for pre-, mid-, and post-tests using the Physical Activity and Leisure Motivation Scale-Youth-Malay (PALMS-Y-M). Mixed factorial ANOVA showed significant changes in enjoyment, F(2, 392) = 8.720, p-value (ηp2) = 0.001 (0.043); competitiveness, F(2, 195) = 4.364, p-value (ηp2) = 0.014 (0.043); appearance, F(2, 392) = 5.709, p-value (ηp2) = 0.004 (0.028); and psychological condition, F(2, 392) = 4.376, p-value (ηp2) = 0.013 (0.022), whereas mastery, affiliation, and physical condition were not significant (p < 0.05). Further post-hoc analysis revealed a significant downward trend in the control group (p < 0.05). Brain breaks is successful in maintaining students' motives for PA in four of the seven factors.

Effects of Isokinetic versus Isotonic Training and its Cessation on Total Leukocytes and Lymphocytes Count in Adolescent State-level Weightlifters

Background:

The study investigated the effects of isokinetic versus isotonic training among adolescent state-level weightlifters in terms of total leukocytes, total lymphocytes, and its subsets following 24 sessions of training program and a month following training program cessation.

Methods:

Nineteen adolescent state-level weightlifters were assigned into isokinetic or isotonic groups. All participants were recruited from a pool of weightlifters with standardized training program provided by their coach. Series of immunological tests were carried out before the commencement, immediately upon the completion, and a month after the cessation of the additional training program to evaluate total leukocytes and lymphocytes count.

Results:

The results revealed a significant time and group interaction and main effects of time on mean total leukocytes (P < 0.05). Mean total leukocytes count at posttest decreased in both groups. In isotonic group, it was further decreased following 1 month of training cessation (P < 0.05) but not in the isokinetic group. However, the decrement was not high and the values were in the normal range. No significant time and group interaction was observed in total lymphocytes and its subsets count.

Conclusions:

Eight weeks of isokinetic and isotonic additional training with emphasis on shoulder joint only affect mean total leukocytes count in state-level adolescent weightlifters.

The effects of combined probiotic ingestion and circuit training on muscular strength and power and cytokine responses in young males

To our knowledge, the efficacy of combined probiotic supplementation with circuit training has not been evaluated. Thus, we investigated the effects of probiotic supplementation combined with circuit training on isokinetic muscular strength and power and cytokine responses in young males. Forty-eight healthy sedentary young males were recruited and randomised into 4 separate groups: sedentary placebo control, probiotics (P), circuit training with placebo (CT), and circuit training with probiotics (CTP). Participants in the CT and CTP groups performed circuit training 3 times/week with 2 circuits of exercises from weeks 1-8 followed by 3 circuits of exercises from weeks 9-12. Participants in the P and CTP groups consumed multi-strain probiotics containing 3 × 10¹⁰ colony-forming units of Lactobacillus acidophilus, L. lactis, L. casei, Bifidobacterium longum, B. bifidum and B. infantis twice daily for 12 weeks. Measurements of body height and weight, blood pressure, resting heart rate, blood samples, and isokinetic muscular strength and power were carried out at pre- and post-tests. Isokinetic knee strength and power in CT and CTP groups were significantly higher (P < 0.05) at post-test. In addition, interleukin (IL)-10 concentration was significantly increased (P < 0.0001) at post-test in P and CT but a trend toward significant increase in CTP (P = 0.09). Nevertheless, there was no significant difference in IL-6. This study suggests that 12 weeks of circuit training alone and the combination of circuit training and probiotic consumption improved muscular performance while circuit training alone and probiotics alone increased IL-10 concentration.

Respiratory infection risk in athletes: association with antigen-stimulated IL-10 production and salivary IgA secretion

The purpose of this study was to examine factors influencing susceptibility to upper respiratory tract infections (URTI) in 18-35-year-old men and women engaged in endurance-based physical activity during the winter months. Eighty individuals (46 males, 34 females) provided resting blood and saliva samples for determination of markers of systemic immunity. Weekly training and illness logs were kept for the following 4 months. Thirty subjects did not experience an URTI episode and 24 subjects experienced 3 or more weeks of URTI symptoms. These illness-prone subjects had higher training loads and had ∼2.5-fold higher interleukin (IL)-4 and IL-10 production by antigen-stimulated whole blood culture than the illness-free subjects. Illness-prone subjects also had significantly lower saliva S-IgA secretion rate and higher plasma IgM (but not IgA or IgG) concentration than the illness-free subjects. There were no differences in circulating numbers of leukocyte subtypes or lymphocyte subsets between the illness-prone and illness-free subjects. The production of IL-10 was positively correlated and the S-IgA secretion rate was negatively correlated with the number of weeks with infection symptoms. It is concluded that high IL-10 production in response to antigen challenge and low S-IgA secretion are risk factors for development of URTI in physically active individuals.