Gait transition speed as an alternate measure of maximum aerobic capacity in fishes

In this study, we report the first allometric equations relating gait parameters and swimming speed to body size for fish employing pectoral fin locomotion. Comparisons of locomotor kinematics and performance among striped surfperch (Teleostei: Embiotocidae) are made at the pectoralcaudal gait transition speed (Up-c). Up-c is considered to elicit physiologically equivalent levels of exercise in animals varying over 100-fold in body mass (Mb) by virtue of dynamically similar pectoral fin movements (constant duty factor, length-specific stride length and fin-beat amplitude) and size-independent propulsive efficiency. At Up-c, pectoral fin-beat frequency scales in proportion to Mb-0.12±0.03, a size-dependence consistent with that observed for stride frequency in fishes swimming by axial undulatory propulsion and in many running tetrapods. It is proposed that the similarity in the scaling of frequency in these vertebrate groups reflects an underlying similarity in the allometry of the maximal velocity of muscle shortening. Absolute Up-c (m s-1) generally increases with body size, but the fastest speeds are not exhibited by the largest animals. A pattern of declining performance in fish 23 cm in standard length and longer may be related to their disproportionately small fin areas and aspect ratios. The pronounced negative allometry of Up-c expressed as standard body lengths per second indicates that a given length-specific speed does not induce comparable levels of activity in large and small fish. Thus, normalization of swimming speed to body length may not be a sufficient correction for kinematic comparisons across size.

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Maximum Aerobic Capacity of Underground Coal Miners in India

Journal of Environmental and Public Health ◽

10.1155/2011/232168 ◽

2011 ◽

Vol 2011 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Ratnadeep Saha ◽

Netai Chandra Dey ◽

Amalendu Samanta ◽

Rajib Biswas

Keyword(s):

Aerobic Capacity ◽

Indirect Method ◽

The Body ◽

Step Test ◽

Maximal Heart Rate ◽

Coal Miners ◽

Test Protocol ◽

Working Groups ◽

Maximum Aerobic Capacity

Miners fitness test was assessed in terms of determination of maximum aerobic capacity by an indirect method following a standard step test protocol before going down to mine by taking into consideration of heart rates (Telemetric recording) and oxygen consumption of the subjects (Oxylog-II) during exercise at different working rates. Maximal heart rate was derived as 220−age. Coal miners reported a maximum aerobic capacity within a range of 35–38.3 mL/kg/min. It also revealed that oldest miners (50–59 yrs) had a lowest maximal oxygen uptake (34.2±3.38 mL/kg/min) compared to (42.4±2.03 mL/kg/min) compared to (42.4±2.03 mL/kg/min) the youngest group (20–29 yrs). It was found to be negatively correlated with age (r=−0.55and −0.33 for younger and older groups respectively) and directly associated with the body weight of the subjects (r=0.57–0.68,P≤0.001). Carriers showed maximum cardio respiratory capacity compared to other miners. Indian minersVO2maxwas found to be lower both compared to their abroad mining counterparts and various other non-mining occupational working groups in India.

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Coronary intercapillary distance during growth: relation to PtO2 and aerobic capacity

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1976.231.6.1852 ◽

1976 ◽

Vol 231 (6) ◽

pp. 1852-1859 ◽

Cited By ~ 24

Author(s):

L Henquell ◽

CL Odoroff ◽

CR Honig

Keyword(s):

Aerobic Capacity ◽

Capillary Density ◽

Left Ventricular ◽

Capillary Recruitment ◽

Tissue Po2 ◽

Intercapillary Distance ◽

Maximum Aerobic Capacity ◽

Effect Of Age

Intercapillary distance (ICD) was measured in left ventricles of rats beating in situ. Between 40 and 400 days of age, left ventricular weight increased threefold and ICD increased from 12.5-19.5 mum. ICD could be decreased by at least 2 mum at all ages studied. The number of capillaries which must be recruited to reduce ICD by 2 mum fell from 1,200/mm2 at 40 days to 280/mm2 at 400 days. Ventricular growth did not affect the O2 sensitivity of precapillary sphincters or the uniformity of capillary spacing. Calculations indicate that under basal conditions tissue PO2 (Pto2) in subepicardium is about the same at 40 and 400 days, even though VO2 per gram, capillary density, and ICD change twofold, twofold, and 7 mum, respectively. Nevertheless, as the ventricle grows, capillary recruitment becomes progressively less effective in defending Pto2 under conditions of stress. Diminished coronary capillary compensation for stress may, in part, account for the effect of age on the maximum aerobic capacity of the whole animal.

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The Use of Gait Transition Speed in Comparative Studies of Fish Locomotion

American Zoologist ◽

10.1093/icb/36.6.555 ◽

1996 ◽

Vol 36 (6) ◽

pp. 555-566 ◽

Cited By ~ 62

Author(s):

ELIOT G. DRUCKER

Keyword(s):

Comparative Studies ◽

Gait Transition ◽

Fish Locomotion ◽

Transition Speed

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Acclimization in a hot, humid environment: cardiovascular adjustments

Journal of Applied Physiology ◽

10.1152/jappl.1976.40.5.779 ◽

1976 ◽

Vol 40 (5) ◽

pp. 779-785 ◽

Cited By ~ 74

Author(s):

C. H. Wyndham ◽

G. G. Rogers ◽

L. C. Senay ◽

D. Mitchell

Keyword(s):

Heart Rate ◽

Cardiac Output ◽

Stroke Volume ◽

Phase I ◽

Skin Temperature ◽

Aerobic Capacity ◽

Heat Exposure ◽

Phase Iii ◽

Humid Environment ◽

Maximum Aerobic Capacity

Four trained young men worked for 4 h/day at 40–50% of their maximum aerobic capacity first for 3 days at 25 degrees C db, 18 degrees C wb, and then for 10 consecutive days at 45 degrees C db, 32 degrees C wb. This portion of the study was mainly concerned with central circulatory changes during acclimatization. The central circulatory adaptation to work in heat could be divided into four distinct phases: phase I (day 1) was characterized by a progressive fall in stroke volume (SV) during heat exposure but cardiac output (CO) was maintained above control values by high heart rates. Phase II (days 2 and 3) was marked by increases in SV ande decreases in heart rate but with little change in CO from phase I. During phase III (days 4–8 of acclimatization), CO increased due to increases in SV. Phase IV (days 6–8) was associated with decreases in rectal and skin temperature towards control levels. SV and HR both decline in this phase so that CO was not elevated greatly above control levels. The results indicated that central circulatory and temperature regulating events are not casually associated in acclimatization.

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Stability Landscapes of Walking and Running Near Gait Transition Speed

Journal of Applied Biomechanics ◽

10.1123/jab.16.4.428 ◽

2000 ◽

Vol 16 (4) ◽

pp. 428-435 ◽

Cited By ~ 32

Author(s):

Li Li

Keyword(s):

Systems Approach ◽

Quantitative Measure ◽

Human Locomotion ◽

Human Motion ◽

Mathematical Representation ◽

Gait Transition ◽

Transition Speed ◽

Acceleration And Deceleration ◽

Transition Change ◽

The Stability

Variability has long been used as an indication of stability in the application of a dynamical systems approach to human motion (i.e., greater variability has been related to a less stable system and vise versa). This paper incorporates the probability of gait transition during walking and running at a certain speed to represent the stability of human locomotion. The mathematical representation concerning the probability of gait transition change with locomotory speed was derived for increasing walking speed and decreasing running speed. Additionally, the influence of acceleration and deceleration on the stability landscapes of walking and running was discussed based on experimental data. The influence of acceleration was also used to explain the different trends of hysteresis observed by various researchers. Walk-to-run transition speed was greater than run-to-walk transition speed, with a greater magnitude of acceleration, while the trend was reversed with a lesser acceleration magnitude. The quantitative measure of the relationship between variability and stability needs to be explored in the future.

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Efficacy of a Botanical Supplement with Concentrated Echinacea purpurea for Increasing Aerobic Capacity

ISRN Nutrition ◽

10.1155/2014/149549 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

David Bellar ◽

Kaitlyn M. Moody ◽

Nicholas S. Richard ◽

Lawrence W. Judge

Keyword(s):

Physical Activity ◽

Aerobic Capacity ◽

Experimental Period ◽

Echinacea Purpurea ◽

Test Analysis ◽

Paired Samples ◽

Significant Difference ◽

Maximum Aerobic Capacity ◽

Physical Activity And Exercise ◽

Botanical Supplements

The present investigation evaluated the efficacy of a botanical supplement that delivered a concentrated dose of Echinacea purpurea (8 grams day−1). The participants were 13 apparently healthy, recreationally active college students (VO2 max: 51 mL O2/kg*min). The participants were provided with a 30-day supplementation regime. Data regarding maximum aerobic capacity was collected through pre- and posttesting surrounding the 30-day supplementation regime. The participants were instructed to maintain normal levels of physical activity and exercise during the experimental period. The levels of physical activity and exercise were monitored via the Leisure and Physical Activity Survey. The participants did not report any significant increases in aerobic physical activity or exercise during the supplementation period. Paired samples t-test analysis did not reveal a significant difference in maximum aerobic capacity, t12=0.67, P=.516. Presupplementation maximum aerobic capacity (M=51.0, SD=6.8) was similar to postsupplementation values (M=51.8, SD=6.5). This study suggests that botanical supplements containing a concentrated dose of Echinacea purpurea is not an effective intervention to increase aerobic capacity of recreationally active individuals.

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THE EFFECT OF AEROBIC GYMNASTIC TRAINING AT MENSTRUAL CYCLE PHASE AND PERCEPTION ON MAXIMUM AEROBIC CAPACITY

10.31227/osf.io/zv3rm ◽

2018 ◽

Author(s):

Umar Nawawi

Keyword(s):

Menstrual Cycle ◽

Aerobic Capacity ◽

Sampling Technique ◽

Female Students ◽

Cycle Phase ◽

Positive Perception ◽

Menstrual Cycle Phase ◽

Negative Perception ◽

Significant Difference ◽

Maximum Aerobic Capacity

This study was intended to investigate the effect of aerobic gymnastic training at the menstrual cycle phase and perceptions of female students of Sport Science Faculty of State University of Padang on maximum aerobic capacity. The research was conducted using repeated factorial design 2 x 3. Aerobic gymnastic training was a treatment given to the menstrual cycle phase as independent variables, perception as the attribute variable, and the maximum aerobic capacity as the dependent variable. 40 students were taken by using purposive sampling technique as the samples from 170 female students enrolled at 2010/2011 academic year. The data of menstrual cycle phase and perception were collected by using questionnaires while the data of maximum aerobic capacity were taken by using MSFT (beep test). The data of maximum aerobic capacity were then analyzed using by inferential statistics ANOVA 2 x 3 two paths .The data analysis and interpretation indicate that: (1) as the whole, there is a significant difference of the effect of aerobic gymnastic training during premenstrual, menstrual, and postmenstrual phases on the maximum aerobic capacity; (2) there is an interaction between the effects of aerobic gymnastic training during the menstrual phases and the perception on maximum aerobic capacity; (3) there is no significant effect of aerobic gymnastic training during premenstrual and menstrual phases of the students whose positive perception on maximum aerobic capacity; (4) there is a significant effect of aerobic gymnastic training during premenstrual and postmenstrual phases of the female students whose positive perception on maximum aerobic capacity; (5) there is no significant effect of aerobic gymnastic training during menstrual and postmenstrual phases of the female students whose positive perception on maximum aerobic capacity; (6) there is a significant effect of aerobic gymnastic training during premenstrual and menstrual phases of the female students whose negative perception on maximum aerobic capacity; (7) there is no significant effect of aerobic gymnastic training during premenstrual and postmenstrual phases of the female students whose positive perception on maximum aerobic capacity; and (8) there is a significant effect of aerobic gymnastic training during menstrual and postmenstrual phases of the female students whose negative perception on maximum aerobic capacity. The findings imply that the lowness of maximum aerobic capacity of the students during menstruation is not mainly due to the menstruation itself but more to the negative perception during on the maximum aerobic capacity. Therefore, the teachers, lecturers, and trainers are expected to provide the female students (at any levels of education) with better explanation on the menstrual cycle phases and their effects on physical activities (sports)

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THE EFFECTS OF PHYSICAL EXERCISE THROUGH GAME-MODEL AND CIRCUIT-MODEL EXERCISES APPROACH ON THE MAXIMUM AEROBIC CAPACITY

10.31227/osf.io/b2gfy ◽

2018 ◽

Author(s):

umar nawawi ◽

Alnedral

Keyword(s):

Physical Exercise ◽

Aerobic Capacity ◽

Circuit Model ◽

Game Model ◽

Maximum Aerobic Capacity

This study was intended to analyze the effect of physical exercise through game-model and circuit model exercises approach on the maximum aerobic capacity

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