Effect of Exercise Modality and Intensity on Postexercise Interleukin-6 and Hepcidin Levels

The effect of exercise modality and intensity on Interleukin-6 (IL-6), iron status, and hepcidin levels was investigated. Ten trained male triathletes performed 4 exercise trials including low-intensity continuous running (L-R), low-intensity continuous cycling (L-C), high-intensity interval running (H-R), and high-intensity interval cycling (H-C). Both L-R and L-C consisted of 40 min continuous exercise performed at 65% of peak running velocity (vVO2peak) and cycling power output (pVO2peak), while H-R and H-C consisted of 8 × 3-min intervals performed at 85% vVO2peak and pVO2peak. Venous blood samples were drawn pre-, post-, and 3 hr postexercise. Significant increases in postexercise IL-6 were seen within each trial (p < .05) and were significantly greater in H-R than L-R (p < .05). Hepcidin levels were significantly elevated at 3 hr postexercise within each trial (p < .05). Serum iron levels were significantly elevated (p < .05) immediately postexercise in all trials except L-C. These results suggest that, regardless of exercise mode or intensity, postexercise increases in IL-6 may be expected, likely influencing a subsequent elevation in hepcidin. Regardless, the lack of change in postexercise serum iron levels in L-C may indicate that reduced hemolysis occurs during weight-supported, low-intensity activity.

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Inhibition rather than Enhancement of Hemostatic System Activation during Initiation of Oral Anticoagulant Treatment

Thrombosis and Haemostasis ◽

10.1055/s-0038-1656034 ◽

1997 ◽

Vol 77 (04) ◽

pp. 685-689 ◽

Cited By ~ 11

Author(s):

Paul A Kyrle ◽

Johannes Brockmeier ◽

Ansgar Weltermann ◽

Sabine Eichinger ◽

Wolfgang Speiser ◽

...

Keyword(s):

High Intensity ◽

Oral Anticoagulant ◽

Protein C ◽

Venous Blood ◽

Rapid Decline ◽

Oral Anticoagulant Treatment ◽

Shed Blood ◽

Low Intensity ◽

Hemostatic System ◽

System Activation

SummaryCoumarin-induced skin necrosis is believed to be due to a transient hypercoagulable state resulting from a more rapid decline of the protein C activity relative to that of coagulation factors (F) II, IX and X during initiation of oral anticoagulant therapy. We studied hemostatic system activation during early oral anticoagulant treatment with a technique that investigates coagulation activation in the microcirculation.We determined in 10 healthy volunteers the concentrations of prothrombin fragment F1+2 (f1.2) and thrombin-antithrombin complex (TAT) in blood emerging from an injury of the microvasculature (bleeding time incision) before and after initiation of both high-inten- sity and low-intensity coumarin therapy. In addition, f1.2, TAT, activated F VII (F Vila) and the activities of FII, F VII, F X and protein C were measured in venous blood.A rapid decline of F VII and protein C was observed in venous blood with activities at 24 h of 7 ± 1% and 43 ± 2%, respectively, during the high-intensity regimen. A 20 to 30% reduction of f1.2 and TAT was seen in venous blood at 72 h with no major difference between the high- and the low-intensity regimen. F Vila levels were substantially affected by anticoagulation with a >90% reduction at 48 h during the high-intensity regimen. Following high-intensity coumarin, a >50% decrease in the fl.2 and TAT levels was found in shed blood at 48 h suggesting substantial inhibition of thrombin generation during early oral anticoagulation. An increase in the f1.2 and TAT levels was seen neither in shed blood nor in venous blood.Our data do not support the concept of a transient imbalance between generation and inhibition of thrombin as the underlying pathomechanism of coumarin-induced skin nekrosis.

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Comparing the Effects of Immersed Versus Land-Based High-Intensity Interval Cycling on Energy Intake, Appetite Sensations and Perceived Exertion Among Healthy Men

Perceptual and Motor Skills ◽

10.1177/00315125211007345 ◽

2021 ◽

pp. 003151252110073

Author(s):

Lore Metz ◽

Laurie Isacco ◽

Maud Miguet ◽

Pauline Genin ◽

David Thivel ◽

...

Keyword(s):

Energy Intake ◽

High Intensity ◽

Perceived Exertion ◽

Area Under The Curve ◽

Macronutrient Intake ◽

Healthy Men ◽

High Intensity Interval ◽

Interval Cycling ◽

Desire To Eat ◽

The Relationship

Immersed exercise has been shown to induce higher energy expenditure and no difference or increase in food intake compared with similar exercise on land. In this study, we compared the effects of acute high-intensity cycling performed on land versus when immersed on subsequent energy intake (EI), appetite sensations and perceived exertion (RPE) in healthy men. Ten participants in a postprandial condition completed three experimental visits in a randomized order: a control condition (CONT); a high-intensity interval cycling exercise performed on land (HIIE-L) and the same exercise while immersed in water (HIIE-A) with a similar targeted heart rate. We observed no difference in energy and macronutrient intake and in area under the curve (AUC) for appetite sensations between sessions. The RPE at the end of HIIE-L was negatively correlated with EI (r=–0.67; p < 0.05), AUC for hunger (r=–0.86, p < 0.01), desire to eat (r=–0.78, p < 0.05) and prospective food consumption (r=–0.86, p < 0.01). Conversely, the RPE at the end of HIIE-L was positively correlated with AUC for fullness (r = 0.76 , p < 0.05). No such correlations were observed for HIIE-A. The present study was the first to observe that immersion did not influence EI after HIIE cycling, but immersion blunted the relationship between session RPE and subsequent energy intake and appetite sensations relative to HIIE on land.

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Cerebrovascular Response to an Acute Bout of Short Interval High Intensity Interval Exercise and Recovery in Healthy Adults

10.1101/2021.05.05.21256704 ◽

2021 ◽

Author(s):

Alicen A. Whitaker ◽

Stacey E. Aaron ◽

Carolyn S. Kaufman ◽

Brady K. Kurtz ◽

Stephen X. Bai ◽

...

Keyword(s):

High Intensity ◽

Short Interval ◽

Healthy Adults ◽

Acute Bout ◽

Interval Exercise ◽

Low Intensity ◽

The Third ◽

Secondary Objective ◽

High Intensity Interval ◽

End Tidal

Introduction: High intensity interval exercise (HIIE) is performed widely. However, the field possesses limited knowledge regarding the acute HIIE cerebrovascular response. Our objective was to characterize the middle cerebral artery blood velocity (MCAv) response during an acute bout of short interval HIIE in healthy adults. We hypothesized MCAv would decrease below BL 1) during HIIE, 2) following HIIE, 3) and 30-minutes after HIIE. As a secondary objective, we investigated sex differences in the MCAv response during HIIE. Methods: Fourteen healthy adults (7 male) completed the HIIE session. The 10-minute HIIE session included alternating 1-minute bouts of high-intensity and low-intensity intervals. MCAv, mean arterial pressure (MAP), heart rate (HR), and expired end tidal carbon dioxide (PETCO2), were recorded at BL, during HIIE, following HIIE, and 30-minutes after HIIE. Results: Contrary to our hypothesis, MCAv remained above BL for the HIIE duration. MCAv peaked at the third minute then decreased concomitantly with PETCO2. MCAv was lower than BL after HIIE (p=0.03). Thirty minutes after HIIE, MCAv returned to near BL values (p = 0.47). Women showed higher BL MCAv (x = 70.9 ± 8.1 cm/s) compared to men (x = 59.3 ± 5.8 cm/s, p = 0.01). A greater magnitude of MCAv response was observed in men resulting in non-significant differences during HIIE secondary to higher workload (p = 0.03). Conclusions: Collectively, these findings show that in healthy adults, MCAv remained above BL during a 10-minute short-interval HIIE and returned to resting values 30 minutes after exercise.

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