The metabolic power required to support body weight and accelerate body mass changes during walking on uphill and downhill slopes

The biomechanical and metabolic demands of human running are distinctly affected by velocity and body weight. As runners increase velocity, ground reaction forces (GRF) increase, which may increase the risk of an overuse injury, and more metabolic power is required to produce greater rates of muscular force generation. Running with weight support attenuates GRFs, but demands less metabolic power than normal weight running. We used a recently developed device (G-trainer) that uses positive air pressure around the lower body to support body weight during treadmill running. Our scientific goal was to quantify the separate and combined effects of running velocity and weight support on GRFs and metabolic power. After obtaining this basic data set, we identified velocity and weight support combinations that resulted in different peak GRFs, yet demanded the same metabolic power. Ideal combinations of velocity and weight could potentially reduce biomechanical risks by attenuating peak GRFs while maintaining aerobic and neuromuscular benefits. Indeed, we found many combinations that decreased peak vertical GRFs yet demanded the same metabolic power as running slower at normal weight. This approach of manipulating velocity and weight during running may prove effective as a training and/or rehabilitation strategy.

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Independent metabolic costs of supporting body weight and accelerating body mass during walking

Journal of Applied Physiology ◽

10.1152/japplphysiol.00734.2004 ◽

2005 ◽

Vol 98 (2) ◽

pp. 579-583 ◽

Cited By ~ 114

Author(s):

Alena Grabowski ◽

Claire T. Farley ◽

Rodger Kram

Keyword(s):

Body Weight ◽

Metabolic Rate ◽

Body Mass ◽

Center Of Mass ◽

Metabolic Cost ◽

Added Mass ◽

Normal Walking ◽

Reduced Gravity ◽

The Cost ◽

Support Body Weight

The metabolic cost of walking is determined by many mechanical tasks, but the individual contribution of each task remains unclear. We hypothesized that the force generated to support body weight and the work performed to redirect and accelerate body mass each individually incur a significant metabolic cost during normal walking. To test our hypothesis, we measured changes in metabolic rate in response to combinations of simulated reduced gravity and added loading. We found that reducing body weight by simulating reduced gravity modestly decreased net metabolic rate. By calculating the metabolic cost per Newton of reduced body weight, we deduced that generating force to support body weight comprises ∼28% of the metabolic cost of normal walking. Similar to previous loading studies, we found that adding both weight and mass increased net metabolic rate in more than direct proportion to load. However, when we added mass alone by using a combination of simulated reduced gravity and added load, net metabolic rate increased about one-half as much as when we added both weight and mass. By calculating the cost per kilogram of added mass, we deduced that the work performed on the center of mass comprises ∼45% of the metabolic cost of normal walking. Our findings support the hypothesis that force and work each incur a significant metabolic cost. Specifically, the cost of performing work to redirect and accelerate the center of mass is almost twice as great as the cost of generating force to support body weight.

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Must Desert Chukars (Alectoris chukar sinaica) Drink Water? Water Influx and Body Mass Changes in Response to Dietary Water Content

The Auk ◽

10.1093/auk/101.1.47 ◽

1984 ◽

Vol 101 (1) ◽

pp. 47-52 ◽

Cited By ~ 14

Author(s):

A. Allan Degen ◽

Berry Pinshow ◽

Peter J. Shaw

Keyword(s):

Drinking Water ◽

Body Mass ◽

Free Water ◽

Energy Requirements ◽

Fresh Matter ◽

Alectoris Chukar ◽

Water Influx ◽

Green Vegetation ◽

Body Mass Changes ◽

Vegetation Water

Abstract The Chukar subspecies Alectoris chukar sinaica inhabits the Negev desert, which is characterized by hot, dry summers, and little winter rainfall. Vegetation is dry and dormant during the summer and autumn; green, succulent vegetation is available following winter rain. We studied whether or not and under what dietary conditions Chukars require drinking water. Four groups of Chukars in an outdoor aviary received either a dry ration + water, a dry ration + green vegetation, a dry ration + green vegetation + water, or green vegetation only. The birds offered only greens lost 15% of their body mass in the first 8 days and 2.9% over the next 6 days, while birds on the other three treatments maintained body mass. The birds receiving only greens had the highest total body water to body mass ratio and the highest water influx. We concluded that the Chukars receiving only green vegetation met their water requirements but not their maintenance energy requirements. Chukars fulfilled both their water and energy requirements on a dry ration + green vegetation (without drinking water); the green vegetation comprised approximately 60% of their total fresh matter intake, or 26% of their total dry matter intake. Our analysis suggests that wild desert Chukars do not require drinking water from early winter to late spring, when succulent forage is available, but probably need free water during summer and autumn, when the bulk of their diet is seeds.

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Body Mass, Physical Activity and Eating Habits Changes during the First COVID-19 Pandemic Lockdown in Poland

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18115682 ◽

2021 ◽

Vol 18 (11) ◽

pp. 5682

Author(s):

Hubert Dobrowolski ◽

Dariusz Włodarek

Keyword(s):

Physical Activity ◽

Body Weight ◽

Body Mass ◽

Social Life ◽

Eating Habits ◽

High Energy ◽

High Energy Density ◽

Average Weight ◽

Study Participants ◽

The Impact

The outbreak of the COVID-19 pandemic caused a number of changes in social life around the world. In response to the growing number of infections, some countries have introduced restrictions that may have resulted in the change of the lifestyle. The aim of our study was to investigate the impact of the lockdown on body weight, physical activity and some eating habits of the society. The survey involving 183 people was conducted using a proprietary questionnaire. The mean age of the study participants was 33 ± 11 and mean height 169 ± 8 cm. An average increase in body weight was observed in 49.18% by 0.63 ± 3.7 kg which was the result of a decrease in physical activity and an increase in food consumption. We also observed a decrease in PAL from 1.64 ± 0.15 to 1.58 ± 0.13 and changes in the amount of food and individual groups of products consumption, including alcohol. Among the study participants who did not lose body mass, there was an average weight gain of 2.25 ± 2.5 kg. In conclusion, an increase of weight was shown in about half of the respondents in the study group which was associated with a decrease in physical activity and an increase in the consumption of total food and high energy density products.

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Effects of Triphala on Lipid and Glucose Profiles and Anthropometric Parameters: A Systematic Review

Journal of Evidence-Based Integrative Medicine ◽

10.1177/2515690x211011038 ◽

2021 ◽

Vol 26 ◽

pp. 2515690X2110110

Author(s):

Wiraphol Phimarn ◽

Bunleu Sungthong ◽

Hiroyuki Itabe

Keyword(s):

Body Mass Index ◽

Body Weight ◽

Blood Glucose ◽

Waist Circumference ◽

Lipid Profile ◽

Body Mass ◽

The Body ◽

Current Evidence ◽

Diabetic Patients ◽

Anthropometric Parameters

Aim. The efficacy of triphala on lipid profile, blood glucose and anthropometric parameters and its safety were assessed. Methods. Databases such as PubMed, ScienceDirect, Web of Science, and Thai Library Integrated System (ThaiLIS) were systematically searched to review current evidence of randomized controlled trials (RCT) on triphala. RCTs investigating the safety and efficacy of triphala on lipid profile, blood glucose and anthropometric parameters were included. Study selection, data extraction, and quality assessment were performed independently by 2 authors. Results. Twelve studies on a total of 749 patients were included. The triphala-treated groups showed significantly reduced low-density lipoprotein-cholesterol, total cholesterol and triglyceride in 6 studies. Five RCTs demonstrated triphala-treated groups led to statistically significant decrease in body weight, body mass index and waist circumference of obese patients. Moreover, triphala significantly decreased fasting blood glucose level in diabetic patients but not in people without diabetes. No serious adverse event associated with triphala was reported during treatment. Conclusions. This review summarized a current evidence to show triphala might improve the lipid profile, blood glucose, the body weight, body mass index and waist circumference under certain conditions. However, large well-designed RCTs are required to confirm this conclusion.

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Correlation of Body Mass Index with Oncologic Outcomes in Colorectal Cancer Patients: A Large Population-Based Study

Cancers ◽

10.3390/cancers13143592 ◽

2021 ◽

Vol 13 (14) ◽

pp. 3592

Author(s):

Chong-Chi Chiu ◽

Chung-Han Ho ◽

Chao-Ming Hung ◽

Chien-Ming Chao ◽

Chih-Cheng Lai ◽

...

Keyword(s):

Colorectal Cancer ◽

Body Mass Index ◽

Body Weight ◽

Body Mass ◽

Survival Rates ◽

Normal Weight ◽

P Value ◽

Administrative Claims ◽

The Impact

It has been acknowledged that excess body weight increases the risk of colorectal cancer (CRC); however, there is little evidence on the impact of body mass index (BMI) on CRC patients’ long-term oncologic results in Asian populations. We studied the influence of BMI on overall survival (OS), disease-free survival (DFS), and CRC-specific survival rates in CRC patients from the administrative claims datasets of Taiwan using the Kaplan–Meier survival curves and the log-rank test to estimate the statistical differences among BMI groups. Underweight patients (<18.50 kg/m2) presented higher mortality (56.40%) and recurrence (5.34%) rates. Besides this, they had worse OS (aHR:1.61; 95% CI: 1.53–1.70; p-value: < 0.0001) and CRC-specific survival (aHR:1.52; 95% CI: 1.43–1.62; p-value: < 0.0001) rates compared with those of normal weight patients (18.50–24.99 kg/m2). On the contrary, CRC patients belonging to the overweight (25.00–29.99 kg/m2), class I obesity (30.00–34.99 kg/m2), and class II obesity (≥35.00 kg/m2) categories had better OS, DFS, and CRC-specific survival rates in the analysis than the patients in the normal weight category. Overweight patients consistently had the lowest mortality rate after a CRC diagnosis. The associations with being underweight may reflect a reverse causation. CRC patients should maintain a long-term healthy body weight.

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Post-Kidney Transplant Visit-to-Visit Body Mass Index Variability as a Risk of Post-Transplant Systolic Hypertension

Current Developments in Nutrition ◽

10.1093/cdn/nzaa063_091 ◽

2020 ◽

Vol 4 (Supplement_2) ◽

pp. 1693-1693

Author(s):

Ekamol Tantisattamo ◽

Natnicha Leelaviwat ◽

Natchaya Polpichai ◽

Chawit Lopimpisuth ◽

Sakditad Saowapa ◽

...

Keyword(s):

Body Mass Index ◽

Body Weight ◽

Kidney Transplant ◽

Median Time ◽

Body Mass ◽

Overweight And Obesity ◽

Absolute Difference ◽

Renal Transplant Recipients ◽

Time To Event ◽

Post Transplant

Abstract Objectives Overweight and obesity are associated with hypertension (HTN) in renal transplant recipients (RTR). Body weight variability is known to be associated with HTN and poor cardiovascular (CV) outcomes in diabetic patients. After successful kidney transplantation (KT), weight change is very common due partly to perioperative and immunological factors. Association between body weight variability and HTN in RTR is unknown. We hypothesize that high body weight variability is associated with post-transplant HTN. Methods Body weight variability of RTR from a single transplant center was assessed as visit-to-visit body mass index variability (VVBMIV) by using average successive variability (ASV = the average absolute difference between successive values of BMI measured at 4, 12, 24, 36, and 48 weeks after KT). Multi-variable Cox proportional hazard regression analysis was used to examine association between post-transplant VVBMIV and systolic and diastolic HTN (SHTN and DHTN), which are defined as SBP and DBP ≥130 and 80 mmHg, respectively. Results Of 104 RTR, mean ± SD age was 54.29 ± 11.65 years and 62% were female. The majority (36%) were obese followed by normal weight (33%), and overweight (31%). Incidence of SBP was 0.041 person-weeks and median time to event was 12.86 weeks; while the incidence of DBP was 0.036 person-weeks with a slightly longer median time-to-event of 13 weeks. Mean ASV of BMI was 1.26 ± 0.82 kg/m2 (0.47 to 2.18). Risk of SHTN is increased 32% for every 1 kg/m2 increase in VVBMIV (HR 1.32, 95%CI 1.04 to 1.68, P 0.022). After adjusted for age, gender, and their interaction terms, very 1 kg/m2 increase in VVBMIV is associated with a 29% greater risk of developing SHTN (HR 1.29, 95% CI 1.01 to 1.65, P 0.043). However, increase in VVBMIV is not associated with an increased risk of DHTN for both univariable (HR 1.15, 95%CI 0.88 to 1.49, P 0.308) and multi-variable Cox regressions models (HR 1.13, 95%CI 0.86 to 1.49, P 0.391). Conclusions Post-kidney transplant VVBMIV is independently associated post-transplant SHTN, but not DHTN. Further studies is needed to examine mechanism of body weight variability and blood pressure outcomes in RTR. Funding Sources None.

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Topiramate administration decreases body weight and preserves lean body mass in hemicranic women

e-SPEN the European e-Journal of Clinical Nutrition and Metabolism ◽

10.1016/j.eclnm.2009.03.001 ◽

2009 ◽

Vol 4 (3) ◽

pp. e148-e151

Author(s):

Francesco Di Sabato ◽

Pamela Fiaschetti ◽

Carlina V. Albanese ◽

Roberto Passariello ◽

Filippo Rossi Fanelli ◽

...

Keyword(s):

Body Weight ◽

Lean Body Mass ◽

Body Mass

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Relationship between Body Mass Index, Blood Pressure, and Visual Acuity in Residents of Esan West Local Government Area of Edo State, Nigeria

Physiology Journal ◽

10.1155/2014/510460 ◽

2014 ◽

Vol 2014 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

I. O. Ernest-Nwoke ◽

M. O. Ozor ◽

U. Akpamu ◽

M. O. Oyakhire

Keyword(s):

Blood Pressure ◽

Body Mass Index ◽

Visual Acuity ◽

Body Weight ◽

Local Government ◽

Body Mass ◽

Local Government Area ◽

Cross Sectional ◽

Snellen Chart ◽

Edo State

Aim. To study the relationship between body mass index (BMI) and blood pressure (BP) on visual acuity among apparently healthy residents of Ekpoma, Esan West Local Government Area of Edo State, Nigeria. Methodology. This is a cross-sectional descriptive study among 225 subjects (ages of 18–35 years) from whom BP, body weight, and height were collected. Visual acuity was measured using the Snellen chart following standard procedures of number of letters seen at 6-metre distance. The data were then analyzed using SPSS version 17. Results. The sampled population consists of 112 male and 113 female (mean age 31.72±14.2 years). Majority (180) of the respondents had normal visual acuity. However, compared with the respondents with normal BMI (R19.61±1.5; L19.67±1.70), visual acuity of underweight (R18.53±2.30; L18.53±2.70) and obese (R15.68±4.79; L17.73±1.70) were more deviated. Similarly, compared with respondent with normal BP (120–125/80–85 mmHg; R18.00±2.53; L18.07±3.11), hypotensive (R15.5±7.35; L15.00±10.20), and hypertensive (R15.01±21.25; L15.00±11.91) respondents had deviated visual acuity. Conclusion. Abnormal body weight (underweight and obese) and BP (hypotension and hypertension) have potential negative impacts on visual acuity. Based on the observed relationship between weights, BP, and visual acuity, eye examinations can be included as regular screening exercise for abnormal BMI and BP conditions.

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