scholarly journals Neither Postabsorptive Resting Nor Postprandial Fat Oxidation Are Related to Peak Fat Oxidation in Men With Chronic Paraplegia

2021 ◽  
Vol 8 ◽  
Author(s):  
Kevin A. Jacobs ◽  
David W. McMillan ◽  
Jennifer L. Maher ◽  
James L. J. Bilzon ◽  
Mark S. Nash
Keyword(s):  
Exercise Test ◽  
Fat Oxidation ◽  
Metabolic Health ◽  
Strong Positive Correlation ◽  
Thoracic Spinal Cord ◽  
Important Indicator ◽  
Graded Exercise Test ◽  
Thoracic Spinal ◽  
Cord Injury ◽  
Graded Exercise

The peak rate of fat oxidation (PFO) achieved during a graded exercise test is an important indicator of metabolic health. In healthy individuals, there is a significant positive association between PFO and total daily fat oxidation (FO). However, conditions resulting in metabolic dysfunction may cause a disconnect between PFO and non-exercise FO. Ten adult men with chronic thoracic spinal cord injury (SCI) completed a graded arm exercise test. On a separate day following an overnight fast (≥ 10 h), they rested for 60 min before ingesting a liquid mixed meal (600 kcal; 35% fat, 50% carbohydrate, 15% protein). Expired gases were collected and indirect calorimetry data used to determine FO at rest, before and after feeding, and during the graded exercise test. Participants had “good” cardiorespiratory fitness (VO2peak: 19.2 ± 5.2 ml/kg/min) based on normative reference values for SCI. There was a strong positive correlation between PFO (0.30 ± 0.08 g/min) and VO2peak (r = 0.86, p = 0.002). Additionally, postabsorptive FO at rest was significantly and positively correlated with postprandial peak FO (r = 0.77, p = 0.01). However, PFO was not significantly associated with postabsorptive FO at rest (0.08 ± 0.02 g/min; p = 0.97), postprandial peak FO (0.10 ± 0.03 g/min; p = 0.43), or incremental area under the curve postprandial FO (p = 0.22). It may be advantageous to assess both postabsorptive FO at rest and PFO in those with SCI to gain a more complete picture of their metabolic flexibility and long-term metabolic health.

Determination and validation of peak fat oxidation in endurance‐trained men using an upper body graded exercise test

2019 ◽  
Vol 29 (11) ◽  
pp. 1677-1690 ◽  
Author(s):  
Mikkel Thunestvedt Hansen ◽  
Tue Rømer ◽  
Jacob Frandsen ◽  
Steen Larsen ◽  
Flemming Dela ◽  
...  
Keyword(s):  
Exercise Test ◽  
Fat Oxidation ◽  
Upper Body ◽  
Graded Exercise Test ◽  
Graded Exercise

scholarly journals Menstrual cycle phase does not affect whole body peak fat oxidation rate during a graded exercise test

2020 ◽  
Vol 128 (3) ◽  
pp. 681-687 ◽  
Author(s):  
Jacob Frandsen ◽  
Nina Pistoljevic ◽  
Julia Prats Quesada ◽  
Francisco José Amaro-Gahete ◽  
Christian Ritz ◽  
...  
Keyword(s):  
Menstrual Cycle ◽  
Sex Hormones ◽  
Exercise Test ◽  
Oxidation Rate ◽  
Fat Oxidation ◽  
Whole Body ◽  
Cycle Phase ◽  
Menstrual Cycle Phase ◽  
Graded Exercise Test ◽  
Graded Exercise

Female sex hormones fluctuate in a predictable manner throughout the menstrual cycle in eumenorrheic women. In studies conducted in both animal and humans, estrogen and progesterone have been found to exert individual metabolic effects during both rest and exercise, suggesting that estrogen may cause an increase in fat oxidation during exercise. However, not all studies find these metabolic changes with the natural physiological variation in the sex hormones. To date, no studies have investigated whether whole body peak fat oxidation rate (PFO) and maximal fat oxidation intensity (FATmax) are affected at different time points [mid-follicular (MF), late-follicular (LF), and mid-luteal (ML)] in the menstrual cycle, where plasma estrogen and progesterone are either at their minimum or maximum. We hypothesized that an increased plasma estrogen concentration together with low progesterone concentration in LF would result in a modest but significant increase in PFO. We found no differences in body weight, body composition, or peak oxygen uptake (V̇o2peak) between any of the menstrual phases in the 19 healthy, young eumenorrheic women included in this study. PFO [MF: 0.379 (0.324–0.433) g/min; LF: 0.375 (0.329–0.421) g/min; ML: 0.382 (0.337–0.442) g/min; mean ± (95% CI)] and resting plasma free fatty acid concentrations [MF: 392 (293–492) µmol/l; LF: 477 (324–631) µmol/l; ML: 396 (285–508) µmol/L] were also similar across the menstrual cycle phases. Contrary to our hypothesis, we conclude that the naturally occurring fluctuations in the sex hormones estrogen and progesterone do not affect the whole body PFO and FATmax in young eumenorrheic women measured during a graded exercise test. NEW & NOTEWORTHY Menstrual cycle phase does not affect the peak fat oxidation rate during a graded exercise test. Natural physiological fluctuations in estrogen do not increase peak fat oxidation rate. FATmax is not influenced by menstrual cycle phase in healthy, young eumenorrheic women.

scholarly journals Caffeine increases maximal fat oxidation during a graded exercise test: is there a diurnal variation?

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Mauricio Ramírez-Maldonado ◽  
Lucas Jurado-Fasoli ◽  
Juan del Coso ◽  
Jonatan R. Ruiz ◽  
Francisco J. Amaro-Gahete
Keyword(s):  
Diurnal Variation ◽  
Exercise Test ◽  
Oxidation Rate ◽  
Fat Oxidation ◽  
Time Of Day ◽  
Whole Body ◽  
Caffeine Intake ◽  
Graded Exercise Test ◽  
Graded Exercise ◽  
Maximal Fat Oxidation

Abstract Background There is evidence that caffeine increases the maximal fat oxidation rate (MFO) and aerobic capacity, which are known to be lower in the morning than in the afternoon. This paper examines the effect of caffeine intake on the diurnal variation of MFO during a graded exercise test in active men. Methods Using a triple-blind, placebo-controlled, crossover experimental design, 15 active caffeine-naïve men (age: 32 ± 7 years) completed a graded exercise test four times at seven-day intervals. The subjects ingested 3 mg/kg of caffeine or a placebo at 8 am in the morning and 5 pm in the afternoon (each subject completed tests under all four conditions in a random order). A graded cycling test was performed. MFO and maximum oxygen uptake (VO2max) were measured by indirect calorimetry, and the intensity of exercise that elicited MFO (Fatmax) calculated. Results MFO, Fatmax and VO2max were significantly higher in the afternoon than in the morning (all P < 0.05). Compared to the placebo, caffeine increased mean MFO by 10.7% (0.28 ± 0.10 vs. 0.31 ± 0.09 g/min respectively, P < 0.001) in the morning, and by a mean 29.0% (0.31 ± 0.09 vs. 0.40 ± 0.10 g/min, P < 0.001) in the afternoon. Caffeine also increased mean Fatmax by 11.1% (36.9 ± 14.4 [placebo] vs. 41.0 ± 13.1%, P = 0.005) in the morning, and by 13.1% (42.0 ± 11.6 vs. 47.5 ± 10.8%, P = 0.008) in the afternoon. Conclusion These findings confirm the previously reported diurnal variation in the whole-body fat oxidation rate during graded exercise in active caffeine-naïve men, and indicate that the acute ingestion of 3 mg/kg of caffeine increases MFO, Fatmax and VO2max independent of the time of day. Trial registration NCT04320446. Registered 25 March 2020 - Retrospectively registered

Astaxanthin Supplementation Increases Glutathione Concentrations but Does Not Impact Fat Oxidation During Exercise in Active Young Men

2021 ◽  
pp. 1-8
Author(s):  
Matthew J. McAllister ◽  
Joni A. Mettler ◽  
Kyle Patek ◽  
Matthew Butawan ◽  
Richard J. Bloomer
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Exercise Test ◽  
Young Men ◽  
Advanced Oxidation ◽  
Fat Oxidation ◽  
Advanced Oxidation Protein Products ◽  
Graded Exercise Test ◽  
Graded Exercise ◽  
Markers Of Oxidative Stress

This study investigated the effects of 6 mg/day of astaxanthin supplementation on markers of oxidative stress and substrate metabolism during a graded exercise test in active young men. A double-blind, randomized, counterbalanced, cross-over design was used. Fourteen men (age = 23 ± 2 years) supplemented with 6 mg/day of astaxanthin and a placebo for 4 weeks, with a 1 week washout period between treatments. Following each supplementation period, a fasting blood sample was obtained to measure markers of oxidative stress: glutathione, hydrogen peroxide, advanced oxidation protein products, and malondialdehyde. Participants also completed a graded exercise test after each treatment to determine substrate utilization during exercise at increasing levels of intensity. Glutathione was ∼7% higher following astaxanthin compared with placebo (1,233 ± 133 vs. 1,156 ± 185 μM, respectively; p = .02, d = 0.48). Plasma hydrogen peroxide and malondialdehyde were not different between treatments (p > .05). Although not statistically significant (p = .45), advanced oxidation protein products were reduced by ∼28%. During the graded exercise test, mean fat oxidation rates were not different between treatments (p > .05); however, fat oxidation decreased from 50 to 120 W (p < .001) and from 85 to 120 W (p = .004) in both conditions. Astaxanthin supplementation of 6 mg/day for 4 weeks increased whole blood levels of the antioxidant glutathione in active young men but did not affect oxidative stress markers or substrate utilization during exercise. Astaxanthin appears to be an effective agent to increase endogenous antioxidant status.

scholarly journals The Histopathology of Severe Graded Compression in Lower Thoracic Spinal Cord Segment of Rat, Evaluated at Late Post-injury Phase

2021 ◽  
Author(s):  
Fedorova Jana ◽  
Kellerova Erika ◽  
Bimbova Katarina ◽  
Pavel Jaroslav
Keyword(s):  
Spinal Cord ◽  
Spontaneous Recovery ◽  
Traumatic Injury ◽  
Blue Dye ◽  
Post Injury ◽  
Thoracic Spinal Cord ◽  
Thoracic Spinal ◽  
Severe Traumatic Injury ◽  
Spinal Cord Segment ◽  
Cord Injury

AbstractSpontaneous recovery of lost motor functions is relative fast in rodent models after inducing a very mild/moderate spinal cord injury (SCI), and this may complicate a reliable evaluation of the effectiveness of potential therapy. Therefore, a severe graded (30 g, 40 g and 50 g) weight-compression SCI at the Th9 spinal segment, involving an acute mechanical impact followed by 15 min of persistent compression, was studied in adult female Wistar rats. Functional parameters, such as spontaneous recovery of motor hind limb and bladder emptying function, and the presence of hematuria were evaluated within 28 days of the post-traumatic period. The disruption of the blood-spinal cord barrier, measured by extravasated Evans Blue dye, was examined 24 h after the SCI, when maximum permeability occurs. At the end of the survival period, the degradation of gray and white matter associated with the formation of cystic cavities, and quantitative changes of glial structural proteins, such as GFAP, and integral components of axonal architecture, such as neurofilaments and myelin basic protein, were evaluated in the lesioned area of the spinal cord. Based on these functional and histological parameters, and taking the animal’s welfare into account, the 40 g weight can be considered as an upper limit for severe traumatic injury in this compression model.

scholarly journals Effect of four different forms of high intensity training on BDNF response to Wingate and Graded Exercise Test

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Eugenia Murawska-Ciałowicz ◽  
Gilmara Gomes de Assis ◽  
Filipe Manuel Clemente ◽  
Yuri Feito ◽  
Petr Stastny ◽  
...  
Keyword(s):  
Exercise Test ◽  
High Intensity ◽  
Minute Ventilation ◽  
Interval Training ◽  
Wingate Anaerobic Test ◽  
High Intensity Training ◽  
Graded Exercise Test ◽  
Graded Exercise ◽  
Group 2 ◽  
Intensity Training

AbstractThis study examined the effects of a nine-week intervention of four different high-intensity training modalities [high-intensity functional training (HIFT), high-intensity interval training (HIIT), high-intensity power training (HIPT), and high-intensity endurance training (HIET)] on the resting concentration of brain-derived neurotropic factor (BDNF). In addition, we evaluated the BDNF responses to Graded Exercise Test (GXT) and Wingate Anaerobic Test (WAnT) in men. Thirty-five healthy individuals with body mass index 25.55 ± 2.35 kg/m2 voluntarily participated in this study and were randomly assigned into four training groups. During nine-weeks they completed three exercise sessions per week for one-hour. BDNF was analyzed before and after a GXT and WAnT in two stages: (stage 0—before training and stage 9—after nine weeks of training). At stage 0, an increase in BDNF concentration was observed in HIFT (33%; p < 0.05), HIPT (36%; p < 0.05) and HIIT (38%; p < 0.05) after GXT. Even though HIET showed an increase in BDNF (10%) this was not statistically significant (p > 0.05). At stage 9, higher BDNF levels after GXT were seen only for the HIFT (30%; p < 0.05) and HIIT (18%; p < 0.05) groups. Reduction in BDNF levels were noted after the WAnT in stage 0 for HIFT (− 47%; p < 0.01), HIPT (− 49%; p < 0.001), HIET (− 18%; p < 0.05)], with no changes in the HIIT group (− 2%). At stage 9, BDNF was also reduced after WAnT, although these changes were lower compared to stage 0. The reduced level of BDNF was noted in the HIFT (− 28%; p < 0.05), and HIPT (− 19%;p < 0.05) groups. Additionally, all groups saw an improvement in VO2max (8%; p < 0.001), while BDNF was also correlated with lactate and minute ventilation and selected WAnT parameters. Our research has shown that resting values of BDNF after nine weeks of different forms of high-intensity training (HIT) have not changed or were reduced. Resting BDNF measured at 3th (before GXT at stage 9) and 6th day after long lasting HITs (before WAnT at stage 9) did not differed (before GXT), but in comparison to the resting value before WAnT at the baseline state, was lower in three groups. It appears that BDNF levels after one bout of exercise is depended on duration time, intensity and type of test/exercise.

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