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e-ISSN 1734-2260 from 2005
ISSN 1429-0022 from 1997 till 2004
Indexed in: SportDiscus; EBSCO; Index Copernicus
Medicina Sportiva 2010 vol. 14, Issue 2
Copyright ® 2010 Medicina Sportiva
Dissociation of respiratory sinus arrhythmia and high frequency heart rate variability following exercise
Stephen J. Brown
Read article »
The sustained effect of nasal insufflations on cardio-respiratory, metabolic and performance measures in athletes under respiratory stress
Rachael Mason, Kiri Sharp, Toby Mündel, Stanislav Tatkov, Rodger J Pack
Read article »
Individual training in team sports based on autonomic nervous system activity assessments
Lukas Cipryan, Pavel Stejskal
Read article »
Impact of obesity on quality of life in the elderly
Danielli B. Mello, Estélio Henrique M. Dantas, Mario Luiz P. Verdini, Tania S. Giani, Márcia A. Ferreira, Rogério F. Emygdio, Virginia A. Hortale
Read article »
CAFFEINE DOES NOT CHANGE THE ANAEROBIC PERFORMANCE AND RATE OF MUSCLE FATIGUE IN YOUNG MEN AND WOMEN
Lucas A. Pereira, Jhonata O. Curti, Thiago V. Camata, Ezequiel M. Gonçalves, Sabrina T. Leite, Thiago G. Costa, Andréia Gulak, Gustavo B. Moreno Maia, Antonio C. Moraes, Leandro R. Altimari
Read article »
No Association Between ACE I/D Variation and Endurance Performance Level in Mexican Marathon Runners
Juan R. López-Taylor, Juan L. Martínez, Celia Quiñonez, Thomas D. Fahey, Miguel A. Rivera
Read article »
POST-EXERCISE REHYDRATION: NO CHANGE IN DIURESIS FROM WATER INGESTED AT DIFFERENT TEMPERATURES
Alexandra Pérez-Idárraga, Luis Fernando Aragón-Vargas
Read article »
Sport related compress ion syndromes – review of the literature
Artur Pupka, Justyna Bogdan, Agnieszka Lepiesza, Aleksandra Rojek, Przemysław P. Szyber
Read article »
The benefits of low-friction resistance training in an adolescent baseball player
Steve W. Davison, John F. Caruso, Skyler T. Taylor, Brant M. Lutz, Nathan M. Olson, Melissa L. Mason, David J. Szymanski
Read article »
Dissociation of respiratory sinus arrhythmia and high frequency heart rate variability following exercise
Stephen J. Brown
Introduction: Heart rate variability during recovery from exercise may show a decrease in the high frequency (HF) range, indicative of a decrease in vagal modulation of the heart rate. However, a post-exercise clustering of heart beats during inspiration (respiratory sinus arrhythmia, RSA) potentially improves ventilatory efficiency by matching pulmonary perfusion to alveolar ventilation.
Aim: The purpose of this study was to investigate HRV following a single bout of exercise in trained endurance athletes, while independently quantifying respiratory sinus arrhythmia using simultaneous measures of ventilatory flow and ECG.
Materials and methods: Therefore, in 12 endurance trained males (mean66 ml Kg-1 min-1), both HF and RSA were measured following a single bout of exercise, consisting of 70 min continuous cycle ergometry.
Results: Mean tidal volume was elevated following exercise (0.96 vs. 1.47 L), with no change in breathing frequency. An elevated heart rate following exercise (56 + 2 vs. 70 + 8 beats min-1) had reduced variability in the time domain and in total spectral power, but showed no change in frequency distribution (HF: 30.53 + 16.43 vs. 29.86 + 17.67; low frequency 65.35 + 19.82 vs. 61.66 + 17.63). Before exercise, mean heart rates during inspiration and expiration were 33 + 4 and 24 + 3 beats min-1 respectively. After exercise, mean heart rates during inspiration and expiration were 42 + 6 and 28 + 5 beats min-1 respectively.
Conclusions: A feature of the post-exercise tachycardia was increased clustering of heart beats during inspiration, a finding consistent with an increased respiratory sinus arrhythmia. This may serve to increase the efficiency of ventilation during recovery from exercise.
Key words: cardiac, autonomic nervous system, heart rate, recovery, ventilation
Read article »
The sustained effect of nasal insufflations on cardio-respiratory, metabolic and performance measures in athletes under respiratory stress
Rachael Mason, Kiri Sharp, Toby Münde, Stanislav Tatkov, Rodger J Pack
Introduction: Whilst there are many studies of the benefits of non-invasive respiratory support in cardiovascular and respiratory compromised individuals during the insufflation period, little is known on what effects, if any, remain following the insufflation.
Aim of study: The present study was carried out to investigate the effects of nasal insufflation on various physiological variables and exercise performance in a group of male endurance athletes under respiratory stress.
Materials and methods: Eight male competitive endurance athletes (30 ± 6 yr, VO2max: 65 ± 8 ml kg-1 min-1) were exposed for 30 minutes to: i) 25 L min-1 nasal insufflation with air at 37°C and fully saturated with water, ii) 25 L min-1 nasal insufflation with air at approximately 20°C and 50% relative humidity, and iii) no nasal insufflation and breathing air at approximately 20°C and 50% relative humidity. They then cycled at three five-minute preset work-rates followed by a 15 min self-paced time-trial where they completed as much work as possible.
Results: When pre-treated with air at 37°C and fully saturated with water, there was a significant reduction of the respiratory exchange ratio throughout the pre-set work-rates (P < 0.03) and the amount of work completed in the time-trial was also significantly reduced (P < 0.03).
Conclusion: The possible mechanisms for these long term changes and their potential significance are discussed.
Key words: nasal insufflation, oxygen uptake, respiratory exchange ratio, exercise performance
Read article »
Individual training in team sports based on autonomic nervous system activity assessments
Lukas Cipryan, Pavel Stejskal
The aim of this study was to present inter-individual differences in the reaction of autonomic nervous system (ANS) activity to the same training program, and to thereby support the importance of individual training in team sports during the conditioning period.
Methods: 18 ice hockey players, separated into two groups, were tested. The first group (S1) was composed of 8 players (age 18.0 ± 0.7 years) of a junior ice hockey team. The second group (S2) consisted of 10 players (age 26.7 ± 3.8 years) who were members of an adult ice hockey team. The spectral analysis of heart rate variability (SA HRV) in the orthoclinostatic stimulation was used for the ANS activity assessment. The results of the SA HRV examinations were interpreted by the complex index of the total score (TS), the complex index of vagal activity (VA), the complex index of sympathovagal balance (SVB) and the age-standardized values of the total spectral power (PT). The SA HRV examination took place regularly twice a week over two months of conditioning.
Results: The SA HRV monitoring mostly revealed significant differences in the level of the ANS activity among the players. A number of junior and adult players (P6, P9, P15, and P16) were characterized by almost permanently high ANS activity whereas other players (P4 and P12) occurred below the ANS activity level of healthy individuals.
Conclusion: Based on the evidence of relevant differences in ANS activity, the training efficiency (overreaching and injury reduction) can be positively influenced by creating training groups of players with similar ANS activity. In this sense the coach can make a training program easier if the team consists of players with high ANS activity. Consequently, constructing a sports team based on ANS activity monitoring could play a significant role.
Key words: heart rate variability, conditioning, overtraining, performance
Read article »
Impact of obesity on quality of life in the elderly
Danielli B. Mello, Estélio Henrique M. Dantas, Mario Luiz P. Verdini, Tania S. Giani, Márcia A. Ferreira, Rogério F. Emygdio, Virginia A. Hortale
Objective: The main purpose of this study was to analyze the effect of obesity on Quality of Life (QOL) in the elderly of Rio de Janeiro, Brazil.
Matherial and methods: Setting: participants of the Health Leisure and Social Integration Project (AHLSIP) at the Miécimo da Silva Sport Center in Campo Grande, Rio de Janeiro, Brazil. Design: This research is qualitative - quantitative. Participants: Volunteers (144) with a mean age of 68.03±2.29, physically active and of both genders, participants of the Health Leisure and Social Integration Project (AHLSIP) at the Miécimo da Silva Sport Center in Campo Grande, Rio de Janeiro. Measurements: In the assessment of body composition, the variables used as determinants of overweight/obesity and cardiovascular risk were body mass index (BMI), waist-hip ratio (WHR) and waist circumference (WC), using the protocol and the WHO reference for the elderly (WHO, 2004). And in the assessment of QOL it was used the WHOQOL-OLD.
Results: We observed a significant association between Waist-Hip Ratio (WHR) and the QOL Total Score (P<0.05), showing that individuals with low WHR values had the highest levels of physical activity. We also observed a significant association (P <0.05) between Body Mass Index (BMI) and facet 1 from QOL (P =0,01).
Conclusion: The variables BMI and WHR used in the assessment of body composition as indicators of obesity and risk of body fat distribution have an influence on QOL of aged individuals.
Keywords: obesity, elderly, quality of life (QOL), BMI, WHR, WHOQOL-OLD
Read article »
CAFFEINE DOES NOT CHANGE THE ANAEROBIC PERFORMANCE AND RATE OF MUSCLE FATIGUE IN YOUNG MEN AND WOMEN
Lucas A. Pereira, Jhonata O. Curti, Thiago V. Camata, Ezequiel M. Gonçalves, Sabrina T. Leite, Thiago G. Costa, Andréia Gulak, Gustavo B. Moreno Maia, Antonio C. Moraes, Leandro R. Altimari
Aim: The aim of the study was to investigate the effects of caffeine intake on anaerobic performance and rate of muscle fatigue in young men and women.
Methods: Fourteen recreationally active college students volunteered to the study (7 male, 29.1 ± 2.8 y and 7 female, 22.5 ± 2.9 y) (73.06 ± 13.08 Kg, 173.00 ± 6.90 cm, 24.08 ± 3.01Kg/m2) . The participants performed the Wingate Test (WT) to evaluate the anaerobic performance in two conditions: caffeine (CAF), ingesting 6mg.Kg-1 of caffeine, and placebo (PL), in random order. The variables analyzed during the WT were the Relative Peak Power (W.Kg-1) (RPP), Relative Mean Power (W.Kg-1) (RMP), Fatigue Index (%) (FI) and Peak Power Instant (s) (PPI). EMG signals were analyzed using the Normalized Median Frequency (NMF) to determine the rate of muscle fatigue of the superficial muscles of the Quadriceps Femoris (QF), Rectus Femoris (RF), Vastus Medialis (VM) and Vastus Lateralis (VL). Data analysis was performed using the Student's t test and the two-way ANOVA for repeated measures, followed by the Sheffé post-hoc to compare the results.
Results: Caffeine intake had no effect on anaerobic performance parameters (RPP, RMP, FI and PPI) when compared with placebo (P > 0.05). The rate of muscle fatigue did not change with caffeine intake in the muscles studied (P > 0.05).
Conclusions: Although caffeine may influence endurance and power in short-term, intense exercise; we did not observe such effects in the variables measured in this study.
Key words: 1,3,7-trimethylxanthine, EMG, athletic performance, fatigue, muscle
Read article »
No Association Between ACE I/D Variation and Endurance Performance Level in Mexican Marathon Runners
Juan R. López-Taylor, Juan L. Martínez, Celia Quiñonez, Thomas D. Fahey, Miguel A. Rivera
Introduction and aim of the study: We examined the association between the ACE insertion (I) / deletion (D); (I/D) genotype and endurance performance level in Mexican marathon runners.
Materials and methods: DNA samples were obtained from 437 subjects (men n = 231; women n = 206) who had completed at least two 42 Km road races. Cases; CAS (n = 199; men = 111; women = 88) were finishers in the top 3rd percentile, while controls; CON (n= 238; men = 142; women = 96) were those in the lowest 3rd percentile of their respective age and gender. The DNA sequence variation was detected by the tetra-primer ARMS-PCR procedure. Genotypes were determined by PCR product size. Results: The three expected ACE genotypes were observed in both groups (CON: DD = 27%, ID = 49%, II = 24%; and CAS: DD = 28 %, ID = 41%, II = 31%). These genotype frequencies were in Hardy-Weinberg equilibrium (Χ2, P>0.05) and were not significantly different between genders or groups (Χ2, P>0.05). Allelic frequencies (CON; D = 0.51%, I = 0.49% and CAS; D = 0.49%, I = 0.51) were not significantly different between groups or genders (Χ2, P>0.05). Comparing genotype frequencies by I or D allele carrier status revealed no statistically significant differences (Χ2, P>0.05).
Conclusions: We found no support for the hypothesis of an association between the ACE insertion/deletion polymorphism and endurance performance level in a homogeneous cohort of Mexican marathon runners
Key words: genetics, chromosome 17, athletes, marathon running, endurance, case-control
Read article »
POST-EXERCISE REHYDRATION: NO CHANGE IN DIURESIS FROM WATER INGESTED AT DIFFERENT TEMPERATURES
Alexandra Pérez-Idárraga, Luis Fernando Aragón-Vargas
Aim: to assess the effect of water temperature on post-rehydration urine output and fluid retention
Methods: on three different days, one week apart, 11 physically active men (24±4 years old, 1.73±0.5 m and 70.2±0.9 kg) ( ± S.D.) exercised intermittently in a temperature-controlled room (Dry bulb temperature = 30-32°C, relative humidity = 50-60%) until dehydrated to 1.96±0.2% of body mass (BM) on three separate occasions. They were rehydrated in random order with cold (4-6ºC), ambient (23-25ºC) or warm (38-40ºC) water, equivalent in volume to 120% of weight loss. Fluid was consumed in one hour in 6 equal aliquots, one every 10 minutes. Following rehydration, urine samples were collected every 30 minutes for 4 hours, analyzing volume and Urine Specific Gravity (USG).
Results: no interaction was found between water temperature (TEMP) and diuresis (P=.726), or USG (P=.140) over time. There was no significant effect of TEMP on the total volume of urine eliminated (882±380, 973±341, and 1006±407 mL for cold, ambient, and warm water, respectively; P=.541), or on fluid retention (45.0±22, 41.9±14 and 37±28%; P=.588).
Conclusion: when men are rehydrated with a volume of water equivalent to 120% of weight loss, after dehydration to 2% BM, water temperature (within this range) has no effect on diuresis or fluid retention.
Keywords: recovery, hydration, urine, drinking, water intake
Read article »
Sport related compress ion syndromes – review of the literature
Artur Pupka, Justyna Bogdan, Agnieszka Lepiesza, Aleksandra Rojek, Przemysław P. Szyber
Abstract
Sport related compression syndrome can be defined as the various symptoms related to compression of nerves and vessels by surrounding tissues which appearance or exacerbation is associated with physical activity. A great variety of abnormal compressions of nerves, arteries and rarely veins may appear in athletes and other physically active individuals. Most frequent syndromes are: thoracic outlet syndrome, popliteal artery entrapment syndrome, chronic exertional compartment syndrome, acute exertional compartment syndrome, upper extremity exertional compartment syndrome. They result in exercise-induced pain, swelling of the limb, paresthesias, ischemia and intermittent claudication that can significantly affect athletic performance. Therefore the importance of a careful clinical investigation and early diagnosis should be emphasized to provide appropriate conservative or surgical treatment and prevent further complications. The purpose of this review is to present the anatomy, patophysiology, diagnosis and treatment of theese particular pathologies.
Key words: athletes, TOS, popliteal artery entrapment syndrome, compartment syndrome
Read article »
The benefits of low-friction resistance training in an adolescent baseball player
Steve W. Davison, John F. Caruso, Skyler T. Taylor, Brant M. Lutz, Nathan M. Olson, Melissa L. Mason, David J. Szymanski
Introduction/Aim of the Study: Our case report details the effects of workouts done on a novel low-friction inertial exercise trainer (IET; Impulse Training Systems, Newnan GA) over a 140-day period by a young baseball player to improve his pitch velocity.
Methods: Workouts entailed 32 exercises each performed by the right, and then followed by the left, sides of the body against 3.4 kg of added mass to the IET three times per week. Approximately every two weeks the subject’s performance was measured with two tests. One test assessed pitch velocity with a standard 142 g baseball and calibrated radar gun, while the second measured internal rotation force on the IET with no added mass to the device.
Results: After 140 days, test results showed large maximum internal rotation force (+338%) and pitch velocity (+28%) improvements.
Conclusions: The success of IET workouts likely resulted from high rates of acceleration per repetition and a greater overspeed adaptation than that seen from other training modalities. The IET also imposes a low frictional resistance that limit stresses placed on the maturing skeleton and connective tissues, which may be especially efficacious for a young baseball pitcher’s throwing shoulder. Based upon our results, new research on the effects of the IET to improve baseball pitch velocity is warranted.
Key words: inertial exercise trainer, acceleration, high-speed exercise
Read article »
Indexed in: SportDiscus; EBSCO; Index Copernicus
Dissociation of respiratory sinus arrhythmia and high frequency heart rate variability following exercise
Medicina Sportiva 2010 vol. 14, Issue 2
Copyright ® 2010 Medicina Sportiva
Stephen J. Brown
Read article »
The sustained effect of nasal insufflations on cardio-respiratory, metabolic and performance measures in athletes under respiratory stress
Rachael Mason, Kiri Sharp, Toby Mündel, Stanislav Tatkov, Rodger J Pack
Read article »
Individual training in team sports based on autonomic nervous system activity assessments
Lukas Cipryan, Pavel Stejskal
Read article »
Impact of obesity on quality of life in the elderly
Danielli B. Mello, Estélio Henrique M. Dantas, Mario Luiz P. Verdini, Tania S. Giani, Márcia A. Ferreira, Rogério F. Emygdio, Virginia A. Hortale
Read article »
CAFFEINE DOES NOT CHANGE THE ANAEROBIC PERFORMANCE AND RATE OF MUSCLE FATIGUE IN YOUNG MEN AND WOMEN
Lucas A. Pereira, Jhonata O. Curti, Thiago V. Camata, Ezequiel M. Gonçalves, Sabrina T. Leite, Thiago G. Costa, Andréia Gulak, Gustavo B. Moreno Maia, Antonio C. Moraes, Leandro R. Altimari
Read article »
No Association Between ACE I/D Variation and Endurance Performance Level in Mexican Marathon Runners
Juan R. López-Taylor, Juan L. Martínez, Celia Quiñonez, Thomas D. Fahey, Miguel A. Rivera
Read article »
POST-EXERCISE REHYDRATION: NO CHANGE IN DIURESIS FROM WATER INGESTED AT DIFFERENT TEMPERATURES
Alexandra Pérez-Idárraga, Luis Fernando Aragón-Vargas
Read article »
Sport related compress ion syndromes – review of the literature
Artur Pupka, Justyna Bogdan, Agnieszka Lepiesza, Aleksandra Rojek, Przemysław P. Szyber
Read article »
The benefits of low-friction resistance training in an adolescent baseball player
Steve W. Davison, John F. Caruso, Skyler T. Taylor, Brant M. Lutz, Nathan M. Olson, Melissa L. Mason, David J. Szymanski
Read article »
Dissociation of respiratory sinus arrhythmia and high frequency heart rate variability following exercise
Stephen J. Brown
Introduction: Heart rate variability during recovery from exercise may show a decrease in the high frequency (HF) range, indicative of a decrease in vagal modulation of the heart rate. However, a post-exercise clustering of heart beats during inspiration (respiratory sinus arrhythmia, RSA) potentially improves ventilatory efficiency by matching pulmonary perfusion to alveolar ventilation.
Aim: The purpose of this study was to investigate HRV following a single bout of exercise in trained endurance athletes, while independently quantifying respiratory sinus arrhythmia using simultaneous measures of ventilatory flow and ECG.
Materials and methods: Therefore, in 12 endurance trained males (mean66 ml Kg-1 min-1), both HF and RSA were measured following a single bout of exercise, consisting of 70 min continuous cycle ergometry.
Results: Mean tidal volume was elevated following exercise (0.96 vs. 1.47 L), with no change in breathing frequency. An elevated heart rate following exercise (56 + 2 vs. 70 + 8 beats min-1) had reduced variability in the time domain and in total spectral power, but showed no change in frequency distribution (HF: 30.53 + 16.43 vs. 29.86 + 17.67; low frequency 65.35 + 19.82 vs. 61.66 + 17.63). Before exercise, mean heart rates during inspiration and expiration were 33 + 4 and 24 + 3 beats min-1 respectively. After exercise, mean heart rates during inspiration and expiration were 42 + 6 and 28 + 5 beats min-1 respectively.
Conclusions: A feature of the post-exercise tachycardia was increased clustering of heart beats during inspiration, a finding consistent with an increased respiratory sinus arrhythmia. This may serve to increase the efficiency of ventilation during recovery from exercise.
Key words: cardiac, autonomic nervous system, heart rate, recovery, ventilation
Read article »
The sustained effect of nasal insufflations on cardio-respiratory, metabolic and performance measures in athletes under respiratory stress
Rachael Mason, Kiri Sharp, Toby Münde, Stanislav Tatkov, Rodger J Pack
Introduction: Whilst there are many studies of the benefits of non-invasive respiratory support in cardiovascular and respiratory compromised individuals during the insufflation period, little is known on what effects, if any, remain following the insufflation.
Aim of study: The present study was carried out to investigate the effects of nasal insufflation on various physiological variables and exercise performance in a group of male endurance athletes under respiratory stress.
Materials and methods: Eight male competitive endurance athletes (30 ± 6 yr, VO2max: 65 ± 8 ml kg-1 min-1) were exposed for 30 minutes to: i) 25 L min-1 nasal insufflation with air at 37°C and fully saturated with water, ii) 25 L min-1 nasal insufflation with air at approximately 20°C and 50% relative humidity, and iii) no nasal insufflation and breathing air at approximately 20°C and 50% relative humidity. They then cycled at three five-minute preset work-rates followed by a 15 min self-paced time-trial where they completed as much work as possible.
Results: When pre-treated with air at 37°C and fully saturated with water, there was a significant reduction of the respiratory exchange ratio throughout the pre-set work-rates (P < 0.03) and the amount of work completed in the time-trial was also significantly reduced (P < 0.03).
Conclusion: The possible mechanisms for these long term changes and their potential significance are discussed.
Key words: nasal insufflation, oxygen uptake, respiratory exchange ratio, exercise performance
Read article »
Individual training in team sports based on autonomic nervous system activity assessments
Lukas Cipryan, Pavel Stejskal
The aim of this study was to present inter-individual differences in the reaction of autonomic nervous system (ANS) activity to the same training program, and to thereby support the importance of individual training in team sports during the conditioning period.
Methods: 18 ice hockey players, separated into two groups, were tested. The first group (S1) was composed of 8 players (age 18.0 ± 0.7 years) of a junior ice hockey team. The second group (S2) consisted of 10 players (age 26.7 ± 3.8 years) who were members of an adult ice hockey team. The spectral analysis of heart rate variability (SA HRV) in the orthoclinostatic stimulation was used for the ANS activity assessment. The results of the SA HRV examinations were interpreted by the complex index of the total score (TS), the complex index of vagal activity (VA), the complex index of sympathovagal balance (SVB) and the age-standardized values of the total spectral power (PT). The SA HRV examination took place regularly twice a week over two months of conditioning.
Results: The SA HRV monitoring mostly revealed significant differences in the level of the ANS activity among the players. A number of junior and adult players (P6, P9, P15, and P16) were characterized by almost permanently high ANS activity whereas other players (P4 and P12) occurred below the ANS activity level of healthy individuals.
Conclusion: Based on the evidence of relevant differences in ANS activity, the training efficiency (overreaching and injury reduction) can be positively influenced by creating training groups of players with similar ANS activity. In this sense the coach can make a training program easier if the team consists of players with high ANS activity. Consequently, constructing a sports team based on ANS activity monitoring could play a significant role.
Key words: heart rate variability, conditioning, overtraining, performance
Read article »
Impact of obesity on quality of life in the elderly
Danielli B. Mello, Estélio Henrique M. Dantas, Mario Luiz P. Verdini, Tania S. Giani, Márcia A. Ferreira, Rogério F. Emygdio, Virginia A. Hortale
Objective: The main purpose of this study was to analyze the effect of obesity on Quality of Life (QOL) in the elderly of Rio de Janeiro, Brazil.
Matherial and methods: Setting: participants of the Health Leisure and Social Integration Project (AHLSIP) at the Miécimo da Silva Sport Center in Campo Grande, Rio de Janeiro, Brazil. Design: This research is qualitative - quantitative. Participants: Volunteers (144) with a mean age of 68.03±2.29, physically active and of both genders, participants of the Health Leisure and Social Integration Project (AHLSIP) at the Miécimo da Silva Sport Center in Campo Grande, Rio de Janeiro. Measurements: In the assessment of body composition, the variables used as determinants of overweight/obesity and cardiovascular risk were body mass index (BMI), waist-hip ratio (WHR) and waist circumference (WC), using the protocol and the WHO reference for the elderly (WHO, 2004). And in the assessment of QOL it was used the WHOQOL-OLD.
Results: We observed a significant association between Waist-Hip Ratio (WHR) and the QOL Total Score (P<0.05), showing that individuals with low WHR values had the highest levels of physical activity. We also observed a significant association (P <0.05) between Body Mass Index (BMI) and facet 1 from QOL (P =0,01).
Conclusion: The variables BMI and WHR used in the assessment of body composition as indicators of obesity and risk of body fat distribution have an influence on QOL of aged individuals.
Keywords: obesity, elderly, quality of life (QOL), BMI, WHR, WHOQOL-OLD
Read article »
CAFFEINE DOES NOT CHANGE THE ANAEROBIC PERFORMANCE AND RATE OF MUSCLE FATIGUE IN YOUNG MEN AND WOMEN
Lucas A. Pereira, Jhonata O. Curti, Thiago V. Camata, Ezequiel M. Gonçalves, Sabrina T. Leite, Thiago G. Costa, Andréia Gulak, Gustavo B. Moreno Maia, Antonio C. Moraes, Leandro R. Altimari
Aim: The aim of the study was to investigate the effects of caffeine intake on anaerobic performance and rate of muscle fatigue in young men and women.
Methods: Fourteen recreationally active college students volunteered to the study (7 male, 29.1 ± 2.8 y and 7 female, 22.5 ± 2.9 y) (73.06 ± 13.08 Kg, 173.00 ± 6.90 cm, 24.08 ± 3.01Kg/m2) . The participants performed the Wingate Test (WT) to evaluate the anaerobic performance in two conditions: caffeine (CAF), ingesting 6mg.Kg-1 of caffeine, and placebo (PL), in random order. The variables analyzed during the WT were the Relative Peak Power (W.Kg-1) (RPP), Relative Mean Power (W.Kg-1) (RMP), Fatigue Index (%) (FI) and Peak Power Instant (s) (PPI). EMG signals were analyzed using the Normalized Median Frequency (NMF) to determine the rate of muscle fatigue of the superficial muscles of the Quadriceps Femoris (QF), Rectus Femoris (RF), Vastus Medialis (VM) and Vastus Lateralis (VL). Data analysis was performed using the Student's t test and the two-way ANOVA for repeated measures, followed by the Sheffé post-hoc to compare the results.
Results: Caffeine intake had no effect on anaerobic performance parameters (RPP, RMP, FI and PPI) when compared with placebo (P > 0.05). The rate of muscle fatigue did not change with caffeine intake in the muscles studied (P > 0.05).
Conclusions: Although caffeine may influence endurance and power in short-term, intense exercise; we did not observe such effects in the variables measured in this study.
Key words: 1,3,7-trimethylxanthine, EMG, athletic performance, fatigue, muscle
Read article »
No Association Between ACE I/D Variation and Endurance Performance Level in Mexican Marathon Runners
Juan R. López-Taylor, Juan L. Martínez, Celia Quiñonez, Thomas D. Fahey, Miguel A. Rivera
Introduction and aim of the study: We examined the association between the ACE insertion (I) / deletion (D); (I/D) genotype and endurance performance level in Mexican marathon runners.
Materials and methods: DNA samples were obtained from 437 subjects (men n = 231; women n = 206) who had completed at least two 42 Km road races. Cases; CAS (n = 199; men = 111; women = 88) were finishers in the top 3rd percentile, while controls; CON (n= 238; men = 142; women = 96) were those in the lowest 3rd percentile of their respective age and gender. The DNA sequence variation was detected by the tetra-primer ARMS-PCR procedure. Genotypes were determined by PCR product size. Results: The three expected ACE genotypes were observed in both groups (CON: DD = 27%, ID = 49%, II = 24%; and CAS: DD = 28 %, ID = 41%, II = 31%). These genotype frequencies were in Hardy-Weinberg equilibrium (Χ2, P>0.05) and were not significantly different between genders or groups (Χ2, P>0.05). Allelic frequencies (CON; D = 0.51%, I = 0.49% and CAS; D = 0.49%, I = 0.51) were not significantly different between groups or genders (Χ2, P>0.05). Comparing genotype frequencies by I or D allele carrier status revealed no statistically significant differences (Χ2, P>0.05).
Conclusions: We found no support for the hypothesis of an association between the ACE insertion/deletion polymorphism and endurance performance level in a homogeneous cohort of Mexican marathon runners
Key words: genetics, chromosome 17, athletes, marathon running, endurance, case-control
Read article »
POST-EXERCISE REHYDRATION: NO CHANGE IN DIURESIS FROM WATER INGESTED AT DIFFERENT TEMPERATURES
Alexandra Pérez-Idárraga, Luis Fernando Aragón-Vargas
Aim: to assess the effect of water temperature on post-rehydration urine output and fluid retention
Methods: on three different days, one week apart, 11 physically active men (24±4 years old, 1.73±0.5 m and 70.2±0.9 kg) ( ± S.D.) exercised intermittently in a temperature-controlled room (Dry bulb temperature = 30-32°C, relative humidity = 50-60%) until dehydrated to 1.96±0.2% of body mass (BM) on three separate occasions. They were rehydrated in random order with cold (4-6ºC), ambient (23-25ºC) or warm (38-40ºC) water, equivalent in volume to 120% of weight loss. Fluid was consumed in one hour in 6 equal aliquots, one every 10 minutes. Following rehydration, urine samples were collected every 30 minutes for 4 hours, analyzing volume and Urine Specific Gravity (USG).
Results: no interaction was found between water temperature (TEMP) and diuresis (P=.726), or USG (P=.140) over time. There was no significant effect of TEMP on the total volume of urine eliminated (882±380, 973±341, and 1006±407 mL for cold, ambient, and warm water, respectively; P=.541), or on fluid retention (45.0±22, 41.9±14 and 37±28%; P=.588).
Conclusion: when men are rehydrated with a volume of water equivalent to 120% of weight loss, after dehydration to 2% BM, water temperature (within this range) has no effect on diuresis or fluid retention.
Keywords: recovery, hydration, urine, drinking, water intake
Read article »
Sport related compress ion syndromes – review of the literature
Artur Pupka, Justyna Bogdan, Agnieszka Lepiesza, Aleksandra Rojek, Przemysław P. Szyber
Abstract
Sport related compression syndrome can be defined as the various symptoms related to compression of nerves and vessels by surrounding tissues which appearance or exacerbation is associated with physical activity. A great variety of abnormal compressions of nerves, arteries and rarely veins may appear in athletes and other physically active individuals. Most frequent syndromes are: thoracic outlet syndrome, popliteal artery entrapment syndrome, chronic exertional compartment syndrome, acute exertional compartment syndrome, upper extremity exertional compartment syndrome. They result in exercise-induced pain, swelling of the limb, paresthesias, ischemia and intermittent claudication that can significantly affect athletic performance. Therefore the importance of a careful clinical investigation and early diagnosis should be emphasized to provide appropriate conservative or surgical treatment and prevent further complications. The purpose of this review is to present the anatomy, patophysiology, diagnosis and treatment of theese particular pathologies.
Key words: athletes, TOS, popliteal artery entrapment syndrome, compartment syndrome
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The benefits of low-friction resistance training in an adolescent baseball player
Steve W. Davison, John F. Caruso, Skyler T. Taylor, Brant M. Lutz, Nathan M. Olson, Melissa L. Mason, David J. Szymanski
Introduction/Aim of the Study: Our case report details the effects of workouts done on a novel low-friction inertial exercise trainer (IET; Impulse Training Systems, Newnan GA) over a 140-day period by a young baseball player to improve his pitch velocity.
Methods: Workouts entailed 32 exercises each performed by the right, and then followed by the left, sides of the body against 3.4 kg of added mass to the IET three times per week. Approximately every two weeks the subject’s performance was measured with two tests. One test assessed pitch velocity with a standard 142 g baseball and calibrated radar gun, while the second measured internal rotation force on the IET with no added mass to the device.
Results: After 140 days, test results showed large maximum internal rotation force (+338%) and pitch velocity (+28%) improvements.
Conclusions: The success of IET workouts likely resulted from high rates of acceleration per repetition and a greater overspeed adaptation than that seen from other training modalities. The IET also imposes a low frictional resistance that limit stresses placed on the maturing skeleton and connective tissues, which may be especially efficacious for a young baseball pitcher’s throwing shoulder. Based upon our results, new research on the effects of the IET to improve baseball pitch velocity is warranted.
Key words: inertial exercise trainer, acceleration, high-speed exercise
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