Field versus race pace conditions to provoke exercise-induced bronchoconstriction in elite swimmers: Influence of training background

INFLUENCE OF SQUAT TRAINING ON LOWER LIMB MUSCULAR STRENGTH IN KUNG FU ATHLETES

ABSTRACT Introduction Aerobic and anaerobic skills are essential characteristics in Kung Fu competitions. Research concerning their repercussions on athletes’ body composition has gained emphasis due to increased sports competitiveness. Squat training is used in martial arts, but there are no reports about the results in kung fu practitioners. Objective Investigate the effects of squat training on lower limb strength in Kung Fu athletes. Methods 18 martial arts athletes were randomly divided into dynamic preparation activities with stretching (control), squat and half-squat exercises. Results The paired T-test result of the control subjects was P=0.578, and the paired squat test result, relative to the control group, before and after the experiment was P=0.164. The power gain in the body posture trained with squat was 24.14 z 9.81KG, and in the half squat was 23.10±11.75KG. The strength gain in the body posture with half squat is 29.75±10.79KG versus 20.59±12.59KG in the squat test. Conclusion After six weeks of training, both the squat and half squat groups significantly improved the maximum results of the lower limb strength tests. The muscular strength of athletes is improved throughout the range of motion, reducing the injury risk on the athletes. Evidence Level II; Therapeutic Studies - Investigating the result.

Evaluation of exercise-induced bronchoconstriction and rhinitis in adolescent elite swimmers

OBJECTIVE

Exercise-induced bronchoconstriction (EIB) without asthma and non-allergic rhinitis is frequently reported in athletes who are facing high-risk of airway dysfunctions such as elite swimmers. Therefore, we aimed to evaluate the effect of exercise on nasal and pulmonary functions, additionally to determine the prevalence of EIB and rhinitis in adolescent elite swimmers.

METHODS

The study included 47 adolescent licensed-swimmers (26 males and 21 females) aged between 10 and 17 years old. The prevalence of asthma and allergic disease and the symptom severity scores measured before and after swimming training were assessed through an interview form which includes information related to our study goal. In addition, acoustic rhinometry was utilized to evaluate nasal airway, spirometry was utilized to evaluate EIB in accordance with standard protocols.

RESULTS

Six swimmers had a history of allergic rhinitis (12.8%), while three (6.4%) had asthma. Post-swim mean forced vital capacity (FVC) was significantly higher than pre-swim FVC (p=0.019) and forced expiratory volume 1 (FEV-l)/FVC ratio was significantly lower than pre-swim FEV-l/FVC ratio (p=0.034). In addition, the prevalence of EIB was 8.5%. Moreover, level of nasal discharge statistically increased in post-swim period (p=0.003).

CONCLUSION

We have documented that swimming cause's nasal discharge but do not effect nasal passages. In addition, we observed that the overall prevalence of EIB in swimmers was not different from that of the general population, furthermore swimming exercise significantly increased FVC of swimmers. Therefore, we concluded swimming training can be recommended for children diagnosed with asthma or allergic rhinitis.

The Effect of Different Training Loads on the Lung Health of Competitive Youth Swimmers

Airway hyperresponsiveness (AHR), airway inflammation, and respiratory symptoms are common in competitive swimmers, however it is unclear how volume and intensity of training exacerbate these problems. Thus, our purpose was to measure AHR, inflammation, and respiratory symptoms after low, moderate, and high training loads in swimmers. Competitive youth swimmers (n=8) completed nine weeks of training split into three blocks (Low, Moderate, and High intensity). Spirometry at rest and post-bronchial provocation [Eucapnic Voluntary Hyperpnea (EVH)] and Fractional Exhaled Nitric Oxide (FeNO) were completed at the end of each training block. A weekly self-report questionnaire determined respiratory symptoms. Session Rating of Perceived Exertion (sRPE) quantified internal training loads. Internal load was significantly lower after Moderate training (4840 ± 971 AU) than after High training (5852 ± 737 AU) (p = 0.02, d = 1.17). Pre-EVH FEV₁ was significantly decreased after Moderate (4.52 ± 0.69 L) compared to Low (4.74 ± 0.63 L) (p = 0.025, d = 0.326), but not different from High load. Post-EVH FeNO after Moderate training was significantly decreased (9.4 ± 4.9 ppb) compared to Low training (15.4 ± 3.6 ppb) (p = 0.012, r = 0.884). Respiratory symptom frequency was significantly correlated with percent decrease in FEV₁ 20 minutes post-EVH after Low and Moderate loads (both ρ = -0.71, sig = 0.05), and after High load was significantly correlated with percent decrease in FEV₁ at 10 (ρ = -0.74, sig = 0.03), 15 (ρ = -0.91, sig = 0.00), and 20 minutes post (ρ = -0.75, sig = 0.03). In conclusion, Moderate load training resulted in the worst lung health results, suggesting there may be factors other than the total amount of stress within training blocks that influence lung health. Further research is needed to determine the effect of manipulating specific acute training load variables on the lung health of swimmers.