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1.
Opt Express ; 23(5): 5723-37, 2015 Mar 09.
Article in English | MEDLINE | ID: mdl-25836802

ABSTRACT

The first realization of a wavelength-selective switch (WSS) with direct integration of few mode fibers (FMF) is fully described. The free-space optics FMF-WSS dynamically steers spectral information-bearing beams containing three spatial modes from an input port to one of nine output ports using a phase spatial light modulator. Sources of mode dependent losses (MDL) are identified, analytically analyzed and experimentally confirmed on account of different modal sensitivities to fiber coupling in imperfect imaging and at spectral channel edges due to mode clipping. These performance impacting effects can be reduced by adhering to provided design guidelines, which scale in support of higher spatial mode counts. The effect on data transmission of cascaded passband filtering and MDL build-up is experimentally investigated in detail.

2.
J Sports Med Phys Fitness ; 52(3): 237-44, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22648461

ABSTRACT

AIM: The aim of the study was to measure the physiological demands of a group of high-level female judokas through laboratory tests and field tests (Tatami) and to retest the validity of the Santos test on a different population. METHODS: Eight high-level female judokas participated in the study. Heart rate (HR), maximal oxygen consumption (VO2 max), blood lactate, anaerobic threshold, and ratings of perceived exertion (RPE) were measured using laboratory and field tests that shared common characteristics. RESULTS: The mean (±SD) values obtained in the laboratory tests were HRmax 198.3 (4.1) beats.min-1, VO2 max: 40.9 (7.7) mL.kg-1.min-1, lactate max 9.1 (1.4) mmol.L-1, HR at the anaerobic threshold 171.5 (4.8) beats.min-1, lactate threshold 3.8 (0.4) mmol.L-1, and RPE: 17 (1.1). The mean (±SD) values obtained in the field test were HRmax 199.0 (5.0) beats.min-1, VO2 max: 44.8 (7.3) mL.kg-1.min-1, lactate max: 11.8 (1.5) mmol.l-1, HR at the anaerobic threshold 170.5 (3.2) beats.min-1, lactate threshold: 3.8 (0.1) mmol.L-1, and RPE: 18 (1.4) points. There were no significant differences between the data obtained on both tests in any of the parameters, except for the lactate maximum and VO2 max. CONCLUSION: The Santos test is a helpful instrument for judo training in female athletes. Coaches could use it to design specific training protocols that could help to improve their performance in competition.


Subject(s)
Athletic Performance/physiology , Martial Arts/physiology , Adolescent , Anaerobic Threshold/physiology , Exercise Test/methods , Female , Heart Rate/physiology , Humans , Lactates/blood , Oxygen Consumption/physiology , Physical Endurance/physiology , Physical Exertion/physiology , Reproducibility of Results , Young Adult
3.
J Hum Kinet ; 29: 141-50, 2011 Sep.
Article in English | MEDLINE | ID: mdl-23486994

ABSTRACT

The main goal of this research project was to retest the validity of a specifically designed judo field test (Santos Test) in a different group of judokas. Eight (n=8) national-level male judokas underwent laboratory and field testing. The mean data (mean +/- SD) obtained in the laboratory tests was: HRmax: 200 ± 4.0 beats × min(-1), VO2 max: 52.8 ± 7.9 ± ml × kg(-1) × min(-1), lactate max: 12 ± 2.5 mmol × l(-1), HR at the anaerobic threshold: 174.2 ± 9.4 beats × min(-1), percentage of maximum heart rate at which the anaerobic threshold appears: 87 ± 3.6 %, lactate threshold: 4.0 ± 0.2 mmol × l(-1), and RPE: 17.2 ± 1.0. The mean data obtained in the field test (Santos) was: HRmax: 201.3 ± 4.1 beats × min(-1), VO2 max: 55.6 ± 5.8 ml × kg(-1) × min(-1), lactate max: 15.6 ± 2.8 mmol × l(-1), HR at the anaerobic threshold: 173.2 ± 4.3 beats × min(-1), percentage of maximum heart rate at which the anaerobic threshold appears: 86 ± 2.5 %, lactate threshold: 4.0 ± 0.2 mmol × l(-1), and RPE: 16.7 ± 1.0. There were no significant differences between the data obtained on both tests in any of the parameters, except for maximum lactate concentration. Therefore, the Santos test can be considered a valid tool specific for judo training.

4.
J Strength Cond Res ; 24(9): 2419-28, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20802284

ABSTRACT

The main goal of this research project was to design a specific, simple, and noninvasive field test to determine the individual aerobic-anaerobic transition zone in judokas. Our aim was to develop a field test as close as possible to real judo combat. Eight state- and national-level judokas participated in the study. To find the reliability of our test, all subjects repeated the same test under the same conditions within a 7-day period. Because the results were positive, we tested the validity of our proposal using a laboratory test that possessed the same characteristics. On both tests, the same parameters were studied. The mean data obtained in the laboratory test were as follows: maximum heart rate (HRmax): 198.2 +/- 3.9 bxmin-1, HR at the anaerobic threshold: 170.3 +/- 5.7 bxmin-1, percentage of HRmax at which the anaerobic threshold appears: 85.9 +/- 2.9%, lactate max: 14.6 +/- 1.4 mmolxL-1, lactate threshold: 4 +/- 0.3 mmolxL-1, and VO2max: 58.3 +/- 4.4 mlxkgxmin-1. The mean data obtained in the field test were as follows: HRmax: 199.7 +/- 1.8 bxmin-1, HR at the anaerobic threshold: 169.7 +/- 2.7 bxmin-1, percentage of HRmax at which the anaerobic threshold appears: 85.0 +/- 1.8%, lactate max: 17.0 +/- 2 mmolxL-1, lactate threshold: 4.0 +/- 0.3 mmolxL-1, and VO2max: 59.8 +/- 3.6 mlxkgxmin-1. There were no significant differences between the data obtained on both tests in any of the parameters evaluated, except for the lactate maximum. Therefore, we can conclude that our field test is a useful tool for judo training.


Subject(s)
Anaerobic Threshold/physiology , Martial Arts/physiology , Heart Rate/physiology , Humans , Lactates/blood , Male , Oxygen Consumption/physiology , Physical Exertion/physiology , Reproducibility of Results , Young Adult
5.
Transplant Proc ; 41(3): 1014-5, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19376414

ABSTRACT

The maximal oxygen uptake (VO(2) max) is a standard tool for preoperative counseling of candidates for lung and heart transplantations, as well as an optional measurement to assess liver or renal transplant patients. Also, it provides an objective tool of the functional capacity of posttransplant patients. Exercise limitation and loss of aerobic capacity are common among patients with end-stage liver disease. The functional capacity of these subjects is decreased, as estimated by measuring the VO(2) max in a cardiopulmonary exercise test (CPET). After transplantation improvement is expected in physical capacity. We sought to describe the influence of orthotopic liver transplantation (OLT) on the physical fitness of the recipient at 3 and 12 months after transplantation. Since CPET is an objective test, it is an important tool for clinicians to evaluate patients' functional capacity before and after OLT.


Subject(s)
Exercise/physiology , Forced Expiratory Volume , Liver Diseases/surgery , Liver Transplantation/physiology , Oxygen Consumption , Physical Fitness , Breath Tests , Carbon Dioxide , Counseling , Exercise Test , Female , Follow-Up Studies , Heart Rate , Heart Transplantation/physiology , Humans , Liver Diseases/physiopathology , Male , Spirometry/methods , Time Factors
6.
Article in English | MEDLINE | ID: mdl-9404869

ABSTRACT

Maximal O2 consumption (VO2max) is an index of the capacity for work over an 8 h workshift. Running on a treadmill is the most common method of eliciting it, because it is an easy, natural exercise, and also, by engaging large muscle masses, larger values are obtained than by other exercises. It has been claimed, however, that climbing a laddermill elicits a still higher VO2max, probably because more muscle mass is apparently engaged (legs + arms) than on the treadmill (legs only). However, no data in support of this claim have been presented. To see if differences exist, we conducted progressive tests to exhaustion on 44 active coal miners, on a laddermill (slant angle 75 degrees, vertical separation of rungs 25 cm) and on a treadmill set at a 5% gradient. The subjects' mean (range) age was 37.4 (31-47) years, height 174.3 (164-187) cm, body mass 82.2 (64-103) kg. Mean (range) VO2max on the laddermill was 2.83 (2.31-3.64) l x min(-1) and 2.98 (2.03-4.22) l x min(-1) on the treadmill (P < 0.01, Student's paired t-test). Mean (range) of maximal heart rate f(cmax) (beats x min(-1)) on the laddermill and on the treadmill were 181.0 (161-194) and 181.3 (162-195), respectively (NS). Laddermill:treadmill VO2max was negatively related to both treadmill VO2max x kg body mass(-1) (r = -0.410, P < 0.01) and body mass (r = -0.409, P < 0.01). Laddermill:treadmill f(cmax) was negatively related to treadmill VO2max x kg body mass(-1) (r = -0.367, P < 0.02) but not to body mass (r = -0.166, P = 0.28). Our data would suggest that for fitter subjects (VO2max > 2.6 l x min or VO2max kg body mass(-1) > 30 ml x min(-1) x kg(-1)) and/or higher body masses (> 70 kg), exercise on the laddermill is not dynamic enough to elicit a VO2max as high as on the treadmill. For such subjects, treadmill VO2max would overestimate exercise capacity for jobs requiring a fair amount of climbing ladders or ladder-like structures.


Subject(s)
Exercise Test , Oxygen Consumption , Adult , Arm , Heart Rate , Humans , Leg , Middle Aged
7.
Eur J Appl Physiol Occup Physiol ; 73(3-4): 369-75, 1996.
Article in English | MEDLINE | ID: mdl-8781871

ABSTRACT

Cardiac frequency (fc) was recorded in 101 coal-face miners [mean age 32.7 (range 21-49) years, mean height 169.6 (range 150-185) cm, mean body mass 76.9 (range 54-106) kg, mean maximal cardiac frequency (fcmax) 180.2 (range 154-197) beats min-1, mean maximal oxygen uptake (VO2max) 2.93 (range 1.9-4.0) 1.min-1] with a small-size, nonintrusive fc counter, during the five (n = 76) or at least four (n = 25) work-shifts in a week. The femax and VO2max were determined during a progressive test to exhaustion on a treadmill. Overall (four to five work-shifts) mean work-time fc(fc) was 97.7 (range 74.9-122.4) beats.min-1, resting fc (fcrest) 59.1 (range 50-75) beats.min-1, work-time increase in fc (fc-fcrest) 38.5 (range 21.1-55.8) beats.min-1 and percentage of fe reserve used (fcreserve = fcmax-fcrest) 32.0 (range 18.5-50.9). Multiple regression analysis showed that fc and fc-fcrest, as dependent variables, correlated with predicted percentage of CO lung diffusion capacity, (DLCOSB%) (r = - 0.334 and r = -0.273, respectively) but not with age, fcmax, VO2max, VO2max kg-1 body mass, effort test delta oxygen uptake/delta fe or percentage of forced expiratory volume in 1 s as independent variables. The percentage of fcreserve used as dependent variable, correlated with DLCOSB (r = -0.265) and fcmax (r = -0.227) but not with any of the other variables listed. Individual differences in worktime fc are thus large and virtually unpredictable. Other physiological variables not taken in account here (i.e. sense of effort, fatigue perception) as well as psychological ones (work satisfaction, motivation) may have played a role in those differences. At peaks of effort, some subjects reached fc values within the range of femax.


Subject(s)
Heart Rate/physiology , Mining , Adult , Electrocardiography , Humans , Lung/physiology , Middle Aged , Oxygen Consumption , Physical Exertion/physiology , Regression Analysis
8.
Ergonomics ; 38(6): 1250-63, 1995 Jun.
Article in English | MEDLINE | ID: mdl-7758449

ABSTRACT

Despite the ever-increasing mechanization of industrial activities, coal mining still remains a physically demanding occupation as it is not always possible to extensively mechanize the extraction process. To estimate the physical effort necessary to sustain coal mining activities in a poorly-mechanized mine, cardiac frequency (fc) was measured throughout the working shift with a Sport-Tester PE3000 (Polar Electro OY, Finland) in a representative sample of 73 Asturian miners engaged in a full spectrum of underground work. The mean +/- SD of the overall fc values measured in miners working at the coal face (Group 1, 33 subjects, mean age 32.7 years, age range 21-48 years) was 106.5 +/- 18.2 beats.min-1. In other miners (Group 2, 40 subjects, mean age 34.6 years, age range 23-48 years) corresponding figures were 103.1 +/- 17.7 beats.min-1 (p < 0.05). Subjects' average working shift fc (beats.min-1) was not related to age, measured (treadmill) VO2 max nor VO2 max.kg body weight-1, while average working-shift fc (%fc max) was weakly related to age (r = 0.396, p < 0.05), VO2 max (r = -0.295, p < 0.05) and VO2 max.kg body weight-1 (r = -0.352, p < 0.05). Working-shift peak fc (beats.min-1) was negatively related to age (r = -0.334, p < 0.05). Our study has provided the distribution of the overall fc values likely to be found in subjects working in these poorly-mechanized mines. However, average working-shift fc differs considerably from subject to subject and is largely unpredictable.


Subject(s)
Coal Mining , Heart Rate , Physical Exertion/physiology , Adult , Humans
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