Acute Resistance Exercise Reduces Postprandial Lipemia and Oxidative Stress in Resistance-Trained Men.

ABSTRACT: McAllister, MJ, Steadman, KS, Renteria, LI, Case, MJ, Butawan, MB, Bloomer, RJ, and McCurdy, KW. Acute resistance exercise reduces postprandial lipemia and oxidative stress in resistance-trained men. J Strength Cond Res 36(8): 2139-2146, 2022-Acute ingestion of a high-fat meal (HFM) results in significant increases in postprandial triacylglycerols (TAG) and markers of oxidative stress (OS). Combined aerobic and resistance exercise can attenuate postprandial lipemia; however, it is not clear if acute resistance exercise alone can reduce postprandial OS. The purpose of this study was to determine if acute resistance exercise can attenuate postprandial OS and to compare the effects of moderate versus high-intensity resistance exercise in this regard. Nine ( n = 9) moderately resistance-trained individuals completed 3 testing conditions in a randomized order as follows: (a) rest (no exercise), (b) moderate intensity (3 sets of 10 repetitions at 68% 1 repetition maximum [RM]), and (c) high-intensity resistance exercise (4 sets of 6 repetitions at 85% 1RM). Exercises included barbell back squat, bench press, straight leg deadlift, lat pull-down, upright row, and sit-ups. A HFM was ingested 12 hours after each condition. Blood samples were collected immediately before as well as 2 and 4 hours after ingestion and analyzed for TAG, cholesterol (CHOL), insulin, malondialdehyde (MDA), total nitrate/nitrite (NOx), glutathione (GSH), and advanced oxidation protein products (AOPP). When comparing 4 hour area under curve (AUC) data between conditions, AOPP demonstrated a significantly lower AUC after the moderate-intensity condition compared with resting condition. In addition, resistance exercise resulted in significantly higher plasma NOx concentrations as well as lower TAG and CHOL concentrations after HFM ingestion. Resistance exercise also prevented a decline in GSH that was induced by the HFM. These results demonstrate that acute resistance exercise can attenuate postprandial OS.

A 28-Day Carbohydrate-Restricted Diet Improves Markers of Cardiovascular Disease in Professional Firefighters.

Waldman, HS, Smith, JW, Lamberth, J, Fountain, BJ, Bloomer, RJ, Butawan, MB, and McAllister, MJ. A 28-day carbohydrate-restricted diet improves markers of cardiovascular disease in professional firefighters. J Strength Cond Res 34(10): 2785-2792, 2020-This study compared the effects of a 4-week, nonketogenic, carbohydrate-restricted (<25% of calories) diet (CRD) on markers of inflammation and oxidative stress in professional firefighters (FF). Subjects (n = 15) reported to the laboratory for 2 sessions (i.e., baseline and post-CRD) where blood was drawn from an antecubital vein after a 10-hour overnight fast. Dependent variables measured at baseline and post-CRD included adiponectin, insulin, human growth hormone, cortisol, C-reactive protein, albumin, lipids, glucose, amylase, creatine kinase, malondialdehyde (MDA), advance oxidation protein products (AOPP), total nitrate + nitrite, and soluble intracellular adhesion molecule-1. Compared with baseline, the CRD resulted in dramatic improvements to subjects' cardiometabolic profiles, including decreases in AOPP (51.3 ± 27.3 vs. 32.9 ± 7.9 ng·ml), MDA (1.6 ± 0.6 vs. 1.1 ± 0.5 µmol·L), and triglycerides (84.4 ± 34.4 vs. 64.2 ± 14.4 mg·dl), respectively. In addition, the CRD increased total cholesterol (151.5 ± 23.0 vs. 167.7 ± 38.2 mg·dl) and high-density lipoprotein cholesterol (46.3 ± 12.7 vs. 50.6 ± 15.5 mg·dl), but no differences were found with low-density lipoprotein cholesterol. Overall, our results show a 4-week CRD can favorably improve some markers of cardiovascular health in male FF.

Effects of Curcumin on the Oxidative Stress Response to a Dual Stress Challenge in Trained Men.

Firefighters and military personnel are exposed to a variety of stressors. The combination of mental and physical stress (i.e., dual stress challenges [DSCs]) results in significant oxidative stress (OS), which may contribute to cardiometabolic dysfunction. Curcumin (CUR) is an exogenous antioxidant that may attenuate such OS. Fourteen trained men participated in a randomized, cross-over design to investigate the impact of CUR on markers of OS resulting from DSC. CUR or placebo was ingested three days prior to, and the morning of, testing. The DSC involved 20 min of mental stress challenges during 35 min of cycling at 60% V̇O2 peak. Blood was sampled before, as well as immediately, 30 min, and 60 min after, exercise and analyzed for glutathione (GSH), superoxide dismutase (SOD), hydrogen peroxide (H2O2), and advanced oxidation protein products (AOPP). There was no treatment effect for any variable. However, the DSC resulted in significant reductions in SOD, H2O2, and AOPP at 30 and 60 min after exercise. Previous studies have shown that DSC results in significant OS compared to exercise alone. However, these data suggest the DSC was associated with reductions in postexercise markers of OS. Antioxidant therapy is likely not needed in trained men exposed to DSC.

Acute coffee ingestion with and without medium-chain triglycerides decreases blood oxidative stress markers and increases ketone levels.

Ingestion of ketone supplements, caffeine, and medium-chain triglycerides (MCTs) may all be effective strategies to increase blood levels of the ketone body beta-hydroxybutyrate (D-BHB). However, acute ingestion of a bolus of lipids may increase oxidative stress (OS). The purpose of the study was to investigate the impact of adding varying amounts of MCTs to coffee on blood levels of D-BHB and markers of OS. Ten college-aged men ingested coffee with 0, 28, and 42 g of MCT in a randomized order. Blood samples were collected pre- as well as 2 and 4 h postprandial and analyzed for D-BHB, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), glucose, triglycerides (TAG), insulin, and OS markers: advanced oxidation protein products (AOPP), glutathione (GSH), malondialdehyde (MDA), and hydrogen peroxide (H2O2). All three treatments resulted in a significant increase in D-BHB, HDL-c, and TC as well as a significant decrease in TAG, MDA, H2O2, and insulin. The 42 g treatment was associated with significantly higher levels of AOPP and MDA. Acute ingestion of coffee results in favorable changes to markers of cardiometabolic health that were not impacted by the addition of 28 g of MCT. However, 42 g of MCT caused significantly greater OS.

Effects of psychological stress during exercise on markers of oxidative stress in young healthy, trained men.

PURPOSE: Those engaged in high stress occupations such as firefighters and military personnel are exposed to a variety of psychological and physiological stressors. The combination of mental and physical stress [i.e., dual stress challenges (DSC)] results in significant increases in stress hormones, which causes oxidative stress (OS) and contributes to elevated risk for cardiovascular disease. However, data are needed to determine the impact of DSC on markers of OS in exercise-trained individuals. METHOD: Fourteen healthy trained men aged 21-30 yrs. participated in a randomized, cross-over design to investigate the impact of DSC on blood markers of OS. The exercise alone condition (EA) consisted of 35 min of cycling at 60% V̇O2 peak. The DSC involved 20 min of mental stress challenges during exercise. Blood was sampled before exercise, as well as immediately, and 30 and 60 min after exercise and analyzed for glutathione (GSH), superoxide dismutase (SOD), hydrogen peroxide (H2O2) and advanced oxidation protein products (AOPP). RESULT: No significant treatment × time interactions were found. No time effects were noted for SOD, or H2O2; however, AOPP were reduced at 30 (p = .034) and 60 min post exercise (p = .006). GSH was reduced at 30 (p = .009) and 60 min post exercise (p = .031). CONCLUSION: These results indicate the OS response from DSC is not greater than that produced from EA in exercise trained men. Future work should investigate the impact of chronic resistance and endurance exercise training on OS resulting from DSC.

Effects of Environmental Heat and Antioxidant Ingestion on Blood Markers of Oxidative Stress in Professional Firefighters Performing Structural Fire Exercises.

OBJECTIVE: Firefighters (FFs) involved in fire suppression have the greatest on-duty risk of cardiovascular disease (CVD), which may be caused by oxidative stress (OS). METHODS: Healthy, active FFs performed a victim "search and clear" exercise involving three conditions: (1) no heat, (2) heat + antioxidant, and (3) heat + placebo. Blood samples were analyzed for OS markers glutathione (GSH), oxidized glutathione (GSSG), superoxide dismutase (SOD), catalase (CAT), and advanced oxidation protein products (AOPP). RESULTS: Increased GSH was found during both heat conditions compared with no heat. CAT activity was higher immediately post exercise. AOPP was reduced post exercise. CONCLUSIONS: Antioxidant supplementation did not impact the OS response to exercise. Added heat did not cause OS and exercise resulted in reductions in OS markers. These findings can be attributed to the training status of the FFs involved.

Bio-field array: a dielectrophoretic electromagnetic toroidal excitation to restore and maintain the golden ratio in human erythrocytes.

Erythrocytes must maintain a biconcave discoid shape in order to efficiently deliver oxygen (O2 ) molecules and to recycle carbon dioxide (CO2 ) molecules. The erythrocyte is a small toroidal dielectrophoretic (DEP) electromagnetic field (EMF) driven cell that maintains its zeta potential (ζ) with a dielectric constant (ԑ) between a negatively charged plasma membrane surface and the positively charged adjacent Stern layer. Here, we propose that zeta potential is also driven by both ferroelectric influences (chloride ion) and ferromagnetic influences (serum iron driven). The Golden Ratio, a function of Phi φ, offers a geometrical mathematical measure within the distinct and desired curvature of the red blood cell that is governed by this zeta potential and is required for the efficient recycling of CO2 in our bodies. The Bio-Field Array (BFA) shows potential to both drive/fuel the zeta potential and restore the Golden Ratio in human erythrocytes thereby leading to more efficient recycling of CO2 . Live Blood Analyses and serum CO2 levels from twenty human subjects that participated in immersion therapy sessions with the BFA for 2 weeks (six sessions) were analyzed. Live Blood Analyses (LBA) and serum blood analyses performed before and after the BFA immersion therapy sessions in the BFA pilot study participants showed reversal of erythrocyte rheological alterations (per RBC metric; P = 0.00000075), a morphological return to the Golden Ratio and a significant decrease in serum CO2 (P = 0.017) in these participants. Immersion therapy sessions with the BFA show potential to modulate zeta potential, restore this newly defined Golden Ratio and reduce rheological alterations in human erythrocytes.

Time-restricted feeding of a high-fat diet in male C57BL/6 mice reduces adiposity but does not protect against increased systemic inflammation.

Time-restricted feeding (TRF) limits the duration of food availability without altering diet composition and can combat obesity in humans and mice. For this study we evaluated the effect of timing of food access during a TRF protocol on weight gain, adiposity, and inflammation. Young male C57BL/6 mice were placed on a high-fat (HF) diet (45% fat) for 8 weeks. Food access was unrestricted (HF) or restricted to 6 h per day, either for the first half (HF-early) or the second half (HF-late) of the active phase to resemble a window of time for food consumption early or late in the day in a human population. Weight, obesity-associated parameters, and inflammation were measured. TRF reduced weight gain over the 8-week period in mice consuming the same high-fat diet. Consistent with decreased weight gain in the TRF groups, body fat percentage, liver triglycerides, and plasma leptin and cholesterol levels were reduced. Adipose tissue inflammation, measured by CD11b+F4/80+ macrophage infiltration, was reduced in both TRF groups, but systemic tumor necrosis factor-α was increased in all groups consuming the high-fat diet. The HF-late group gained more weight than the HF-early group and had increased insulin resistance, while the HF-early group was protected. Therefore, a TRF protocol is beneficial for weight management when a high-fat diet is consumed, with food consumption earlier in the day showing greater health benefits. However, increased inflammatory markers in the TRF groups suggest that diet components can still increase inflammation even in the absence of overt obesity.