scholarly journals DOES RAMADAN FASTING AFFECT DIURNAL VARIATION ON SWIMMING PERFORMANCE AND ANAEROBIC POWER?

Author(s):  
Salah Ferchichi ◽  
Yana Taktak

The aim of this study is to see whether Ramadan fasting has an effect on the diurnal variations in anaerobic power and swimming performance or not. Ten participants whose mean ± SE for age, height, body mass are 19.4 ± 1.4 years, 1.72 ± 0.1 m and 72.8 ± 6.6 kg, respectively. They are tested at 3 testing periods [i.e., one week before Ramadan (BR), the middle period of Ramadan (MPR), the end period of Ramadan (EPR)], tests are performed at 07:00 h and 17:00 h throughout every course. The test sessions were started with oral temperature and body mass measurements. Regularly doing first the Wingate test then a 25-m swim at maximal speed at each test session. During the three experimental periods, dietary intake was assessed. The result shows a significant diurnal variation of muscle power and fatigue throughout the Wingate test before Ramadan. Likewise, there is a daily rhythm in the stroke parameters and swimming performance in the mentioned period. These diurnal variations change during the month of Ramadan with a decrease in power output, swim performance, swim speed and stroke length in the evening, with no changes for the morning tests. Moreover, the diurnal variations of muscle fatigue during the three morning tests show no changes and remain the same. Whereas the three evening tests show a gradual increase towards tiredness. The results show that Ramadan may has a great effect on the circadian rhythm of muscle power and swimming performance. The time-of-day effects the anaerobic power variables during the normal days which disappear during Ramadan. Ramadan fasting effects performance in the evening; however, the morning performance tests are unchangeable during Ramadan. Additionally, Ramadan fasting has no adverse effect on energy intake, and percentages of macronutrient intake. <p> </p><p><strong> Article visualizations:</strong></p><p><img src="/-counters-/edu_01/0856/a.php" alt="Hit counter" /></p>

2019 ◽  
Vol 18 (3) ◽  
pp. 118
Author(s):  
Anderson Pontes Morales ◽  
Felipe Sampaio-Jorge ◽  
Thiago Barth ◽  
Alessandra Alegre De Matos ◽  
Luiz Felipe Da Cruz Rangel ◽  
...  

Introduction: The aim of this study was to test the hypothesis that caffeine supplementation (6 mg·kg-1 body mass) for 4-days, followed by acute intake, would impact five male triathletes output power after performed submaximal intensity exercise. Methods: This was a randomized, double-blind, placebo-controlled crossover study, placebo (4-day) - placebo (acute) PP, placebo (4-days) -caffeine (acute) PC, and caffeine (4-day) - caffeine (acute) CC. Participants abstained from dietary caffeine sources for 4 days and ingested capsules containing either placebo or caffeine (6 mg.kg-1 body mass day in one absorption). The acute trials the capsules containing placebo or caffeine (6 mg.kg-1 body mass day in one absorption) were ingested 60min before completing exercise in a treadmill for 40min (80% VO2max) and to perform the Wingate test. Results: Blood lactate was determined before, 60min after ingestion, and immediately after the exercise on the treadmill, the Wingate test, and after the recovery (10-min). CC and PC trials did not change the cardiopulmonary variables (P>0.05) and the anaerobic power variables (peak/mean power output and fatigue index) (P>0.05). The PC trial compared with PP promoted improvements in the curve power output in 2 sec by 31.19% (large effect-size d = 1.08; P<0.05) and 3 sec by 20% (large effect-size d = 1.19; P<0.05). A 10min recovery was not sufficient to reduce blood lactate concentration in the PC trial compared with PP (PC, 13.73±2.66 vs. PP, 10.26±1.60 mmol.L-1; P<0.05, respectively) (P<0.05). Conclusion: In conclusion, these results indicate that caffeine supplementation (6 mg·kg-1 body mass) for 4 days, followed by acute ingestion, did not impact the triathletes output power after performed submaximal intensity exercise. Nutritional interventions may help researchers and athletes to adapt strategies for manipulating caffeine use.Key-words: caffeine metabolism, Wingate test, blood lactate, performance.


2021 ◽  
Vol 65 ◽  
pp. 5-9
Author(s):  
Pooja Kumari ◽  
V Raghunandan ◽  
P Biswal

Introduction: Anthropometric parameters need to be accurately measured because of their direct implications in selection of aircrew, aircrew-cockpit compatibility, and cockpit workspace design. Some of these parameters have significant diurnal variation, hence, measurement of these parameters in particular time of day becomes important. Quantification of these diurnal variations among some of the aviation significant parameters was the desired objective of the study. Material and Methods: In a prospective repeated measure design, anthropometric parameters of a total of 35 volunteers were measured in the standard defined protocol from 0800h to 1600h, at an interval of every 2h, using Institute of Aerospace Medicine (IAM) Anthropometry Platform. The data were analyzed to observe and quantify changes in diurnal variations in both gravity-dependent and gravity-independent parameters. A maximum value of 0.4 cm was taken as intraobserver variations based on the results of a pilot study. Results: There was a statistically significant decrement in the values of gravity-dependent anthropometric parameters from morning to evening; the difference being more after 1200h. Most of the gravity-independent parameters did not show any significant changes from 0800h to 1600h, except leg length, which showed a decrement overtime, the difference being statistically significant after 1200h. Conclusion: The study revealed a statistically significant variation of gravity-dependent anthropometric parameters from the baseline which could be because of the effect of erect posture on the intervertebral disc height and axial compressive loads on the spine. This became practically significant after 1200h. However, most of the gravity-independent parameters did not show any significant variations. Based on the results of this study, anthropometric measurements should be done in the morning hours preferably before 1200h.


2016 ◽  
Vol 47 (3) ◽  
pp. 447-461 ◽  
Author(s):  
Salah Ferchichi ◽  
Yana Taktak ◽  
Heni Taktak ◽  
Hamdi Chtourou ◽  
Fayçal Zarrouk ◽  
...  

2010 ◽  
Vol 24 (1) ◽  
pp. 23-29 ◽  
Author(s):  
Stephen Blonc ◽  
Sébastien Perrot ◽  
Sébastien Racinais ◽  
Stéphane Aussepe ◽  
Olivier Hue

2021 ◽  
pp. 84-85
Author(s):  
Tanuj Mathur ◽  
Dileep Kumar Verma ◽  
Sunita Tiwari ◽  
Narsingh Verma ◽  
Ranjana Singh

Introduction: The purpose of the study was to identify diurnal variations in forced expiratory volume in 1 second (FEV1), Mean Arterial Pressure (MAP) and Body Mass Index (BMI) and a possible association between them. Materials and methods: 40 healthy adults fullling the eligibility criteria were recruited. Spirometric analysis of FEV1 was performed. Results: FEV1 showed statistically signicant differences according to time of day. FEV1 values in the morning was 2.83 + .62 and in the evening, raised to 2.95 + .522 in study population. The highest value was noted in the evening as compared to morning. MAPmean values in the morning was 87.37 + 5.204. MAPmean values in the evening was 88.40 + 7.519, which again showed an increase in the evening. Conclusion: The present study indicated a denite diurnal variation in the pulmonary function and cardiovascular parameter.


Author(s):  
Robin Pla ◽  
Thibaut Ledanois ◽  
Escobar David Simbana ◽  
Anaël Aubry ◽  
Benjamin Tranchard ◽  
...  

The main aim of this study was to evaluate the validity and the reliability of a swimming sensor to assess swimming performance and spatial-temporal variables. Six international male open-water swimmers completed a protocol which consisted of two training sets: a 6×100m individual medley and a continuous 800 m set in freestyle. Swimmers were equipped with a wearable sensor, the TritonWear to collect automatically spatial-temporal variables: speed, lap time, stroke count (SC), stroke length (SL), stroke rate (SR), and stroke index (SI). Video recordings were added as a “gold-standard” and used to assess the validity and the reliability of the TritonWear sensor. The results show that the sensor provides accurate results in comparison with video recording measurements. A very high accuracy was observed for lap time with a mean absolute percentage error (MAPE) under 5% for each stroke (2.2, 3.2, 3.4, 4.1% for butterfly, backstroke, breaststroke and freestyle respectively) but high error ranges indicate a dependence on swimming technique. Stroke count accuracy was higher for symmetric strokes than for alternate strokes (MAPE: 0, 2.4, 7.1 & 4.9% for butterfly, breaststroke, backstroke & freestyle respectively). The other variables (SL, SR & SI) derived from the SC and the lap time also show good accuracy in all strokes. The wearable sensor provides an accurate real time feedback of spatial-temporal variables in six international open-water swimmers during classical training sets (at low to moderate intensities), which could be a useful tool for coaches, allowing them to monitor training load with no effort.


2011 ◽  
Vol 6 (3) ◽  
pp. 419-426 ◽  
Author(s):  
Dale I. Lovell ◽  
Dale Mason ◽  
Elias Delphinus ◽  
Chris McLellan

Purpose:The aim of this study was to compare asynchronous (AS Y) arm cranking (cranks at 180° relative to each other) with synchronous (SYN) arm cranking (parallel crank setting) during the 30 s Wingate anaerobic test.Methods:Thirty-two physically active men (aged 22.1 ± 2.4 y) completed two Wingate tests (one ASY and one SYN) separated by 4 d in a randomized counterbalanced order. The Wingate tests were completed on a modified electromagnetically braked cycle ergometer. Performance measures assessed during the two tests include peak power, mean power, minimum power, time to peak power, rate to fatigue and maximum cadence (RPMmax). Blood lactate concentration was also measured before and 5 min after the tests.Results:Peak and mean power (both absolute and relative to body weight) during SYN arm cranking were significantly (p < 0.001) less than during ASY arm cranking. Rate to fatigue and RPMmax were also significantly (p = 0.012) lower during SYN arm cranking compared with ASY arm cranking. No significant difference was found between test conditions for minimum power, time to peak power or blood lactate concentration.Conclusions:These findings demonstrate that ASY arm cranking results in higher peak and mean anaerobic power compared with SYN arm cranking during the Wingate test. Therefore, an ASY arm crank configuration should be used to assess anaerobic power in most individuals although specific population groups may require further testing to determine which crank configuration is most suitable for the Wingate test.


1872 ◽  
Vol 7 ◽  
pp. 756-758
Author(s):  
J. A. Broun

The author gives the results derived from different discussions of nearly eighty thousand observations, made hourly during the eleven years 1854 to 1864. They are as follows:—1. That the lunar diurnal variation consists of a double maximum and minimum in each month of the year.2. That in December and January the maxima occur near the times of the moon's upper and lower passages of the meridian; while in June and July they occur six hours later, the minima then occurring near the times of the two passages.3. The change of the law for December and January to that for June and July does not happen, as in the case of the solar diurnal variations, by leaps in the course of a month (those of March and October), but more or less gradually for the different maxima and minima.


2007 ◽  
Vol 7 (1) ◽  
pp. 211-222 ◽  
Author(s):  
M. Ehn ◽  
T. Petäjä ◽  
H. Aufmhoff ◽  
P. Aalto ◽  
K. Hämeri ◽  
...  

Abstract. The hygroscopic growth of aerosol particles present in a boreal forest was measured at a relative humidity of 88%. Simultaneously the gas phase concentration of sulfuric acid, a very hygroscopic compound, was monitored. The focus was mainly on days with new particle formation by nucleation. The measured hygroscopic growth factors (GF) correlated positively with the gaseous phase sulfuric acid concentrations. The smaller the particles, the stronger the correlation, with r=0.20 for 50 nm and r=0.50 for 10 nm particles. The increase in GF due to condensing sulfuric acid is expected to be larger for particles with initially smaller masses. During new particle formation, the changes in solubility of the new particles were calculated during their growth to Aitken mode sizes. As the modal diameter increased, the solubility of the particles decreased. This indicated that the initial particle growth was due to more hygroscopic compounds, whereas the later growth during the evening and night was mainly caused by less hygroscopic or even hydrophobic compounds. For all the measured sizes, a diurnal variation in GF was observed both during days with and without particle formation. The GF was lowest at around midnight, with a mean value of 1.12–1.24 depending on particle size and if new particle formation occurred during the day, and increased to 1.25–1.34 around noon. This can be tentatively explained by day- and nighttime gas-phase chemistry; different vapors will be present depending on the time of day, and through condensation these compounds will alter the hygroscopic properties of the particles in different ways.


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