The effects of aerobic and resistant exercises on the lipid profile in healthy women: a systematic review and meta-analysis

Exercise can have a wide range of health benefits, including improving blood lipid profiles. For women to achieve optimal cardiovascular health, it is vital to determine the effect of exercise on their health and whether different exercise intensities can affect their blood lipid profile. A systematic review and meta-analysis were conducted to examine the effects of exercise on improving the lipid profile of healthy women. A database search was conducted using PubMed, Google Scholar, Embase, Scopus, and Web of Science from inception until July 2, 2021, for randomized controlled trials (RCTs) investigating exercise's effects on healthy women's blood lipid profiles. A total of 10 eligible articles (or 17 trials) with 576 participants were identified as eligible for the study. Overall, the meta-analysis shows that physical activity significantly improved total cholesterol (TC), triglycerides (TG), and high-density lipoprotein (HDL-C) levels: TC [WMD = -5.77 mg/dL, 95% CI: -10.41, -1.13, P < 0.01]; TG [WMD = -5.60 mg/dL, 95% CI: -8.96, -2.23, P < 0.01]; HDL [WMD = 4.49 mg/dL, 95% CI: 0.33, 8.65, P = 0.03]. Additionally, sub-group analyses indicated that combined exercise training improved TG and TC (p 0.05), and aerobic exercise significantly increased HDL. In this study, physical activity appears to be one of the most effective non-pharmacological means for improving HDL, TG, and TC in healthy women. In terms of TG and TC, CT was the most effective.

Effect of Prior Exercise on Postprandial Lipemia: An Updated Meta-Analysis and Systematic Review

The purpose of this systematic review was to synthesize the results from current literature examining the effects of prior exercise on the postprandial triglyceride (TG) response to evaluate current literature and provide future direction. A quantitative review was performed using meta-analytic methods to quantify individual effect sizes. A moderator analysis was performed to investigate potential variables that could influence the effect of prior exercise on postprandial TG response. Two hundred and seventy-nine effects were retrieved from 165 studies for the total TG response and 142 effects from 87 studies for the incremental area under the curve TG response. There was a moderate effect of exercise on the total TG response (Cohen's d = -0.47; p < .0001). Moderator analysis revealed exercise energy expenditure significantly moderated the effect of prior exercise on the total TG response (p < .0001). Exercise modality (e.g., cardiovascular, resistance, combination of both cardiovascular and resistance, or standing), cardiovascular exercise type (e.g., continuous, interval, concurrent, or combined), and timing of exercise prior to meal administration significantly affected the total TG response (p < .001). Additionally, exercise had a moderate effect on the incremental area under the curve TG response (Cohen's d = -0.40; p < .0001). The current analysis reveals a more homogeneous data set than previously reported. The attenuation of postprandial TG appears largely dependent on exercise energy expenditure (∼2 MJ) and the timing of exercise. The effect of prior exercise on the postprandial TG response appears to be transient; therefore, exercise should be frequent to elicit an adaptation.

Lipoprotein lipase does not increase significantly in the postprandial plasma

BACKGROUND

Previous reports have shown that lipoprotein lipase (LPL) activity significantly increases in the postprandial plasma associated with the increase of TG-rich lipoproteins. Therefore, we have reexamined those relationships using newly developed LPL assay with the different kinds of food intake.

METHODS

Standard meal (n=81), 50g of fat (n=54), 75g of glucose (n=25) and cookie (25g fat and 75g carbohydrate fat) (n=28) were administered in generally healthy volunteers. Plasma LPL, HTGL and TC, TG, LDL-C, HDL-C, RLP-C and RLP-TG were determined at subsequent withdrawal after the food intake.

RESULTS

Plasma TG, RLP-C and RLP-TG were significantly increased at 8PM (2h after dinner of standard meal) compared with 8AM before breakfast within the same day. Also those parameters were significantly increased in 2-6h after fat load. However, the concentrations and activities of LPL and HTGL did not significantly increase in association with an increase in the TG and remnant lipoproteins. Also LPL concentration did not significantly increase after glucose and "cookie test" within 4h.

CONCLUSION

No significant increase of LPL activity was found at CM and VLDL overload after different kinds of food intake when reexamined by newly developed assay for LPL activity and concentration.

Acute effects of aerobic exercise intensity on arterial stiffness after glucose ingestion in young men

Arterial stiffness increases after glucose ingestion. Acute low- and moderate-intensity aerobic exercise decreases arterial stiffness. However, the acute effects of 30 min of cycling at low- and moderate-intensity [25% (LE trial) and 65% (ME trial) peak oxygen uptake, respectively] on arterial stiffness at 30, 60 and 120 min of a postexercise glucose ingestion. Ten healthy young men (age, 22·4 ± 0·5 years) performed LE and ME trials on separate days in a randomized controlled crossover fashion. Carotid-femoral (aortic) pulse wave velocity (PWV), femoral-ankle (leg) PWV, carotid augmentation index (AIx) and carotid blood pressure (BP) (applanation tonometry), brachial and ankle BP (oscillometric device), heart rate (HR) (electrocardiography), blood glucose (UV-hexokinase method) and blood insulin (CLEIA method) levels were measured at before (baseline) and at 30, 60 and 120 min after the 75-g OGTT. Leg PWV, ankle pulse pressure and BG levels significantly increased from baseline after the 75-g OGTT in the LE trial (P<0·05), but not in the ME trial. Insulin levels and HR significantly increased from baseline after the 75-g OGTT in both trials (P<0·05). Aortic PWV, carotid AIx, brachial BP and carotid BP did not change from baseline after the 75-g OGTT in both trials. The present findings indicate that aerobic exercise at moderate intensity before glucose ingestion suppresses increases leg arterial stiffness after glucose ingestion.

Effects of Aerobic Exercise on Postprandial Carbohydrate and Lipoprotein Metabolism Following Cookie Ingestion in Healthy Young Women

We examined the acute effects of postprandial aerobic exercise on glucose and lipid metabolism following cookie ingestion. Fifteen healthy young women with a sedentary lifestyle, normal weight and apolipoprotein E3/3 participated. After a 12-h overnight fast, each subject ingested a cookie (1.53 g/kg, Meal Test C) and then performed two trials, one with postprandial exercise (E trial) and one without exercise (C trial), in a randomized crossover design. A single 30-min bout of walking exercise was performed 20 min after the cookie intake. Venous blood samples were drawn before (0 h) and 20 min and 1, 2, 4, and 6 h after cookie ingestion. The Δglucose concentration was not significantly different between the two trials, but the Δinsulin concentration at 1 h and the incremental area under the curve (IAUC) (0-2 h)-insulin in the E trial were significantly lower than in the C trial. The ratio of glucose/insulin at 1 h was significantly higher in the E trial than in the C trial. The ΔTG, ΔRLP-TG, ΔapoB48 and ΔRemL-C concentrations at 1 h in the E trial were significantly higher than in the C trial. The IAUC (0-2 h)-apoB48 in the E trial was significantly larger than in the C trial. Postprandial exercise showed an insulin-sparing effect following the cookie ingestion by increasing insulin sensitivity. However, postprandial exercise transiently stimulated the secretion of exogenous apoB48-containing lipoprotein during the early period, and no further effects were observed. These results suggest that postprandial aerobic exercise is effective for the promotion of postprandial carbohydrate metabolism, but not lipidemia.

The Ingestion of a Fructose-Containing Beverage Combined with Fat Cream Exacerbates Postprandial Lipidemia in Young Healthy Women

AIM

To investigate the acute effects of the ingestion of a fructose-containing beverage combinedwith fat on postprandial lipoprotein metabolism.

METHODS

Twelve young healthy Japanese women with apolipoprotein E phenotype 3/3 were enrolled in this study. At each of four sessions, the subjects ingested one of four sugar beverages containing fructose and/or glucose (total: 0.5g/kg body weight) combined with OFTT cream (1g/kg, 0.35g/kg as fat) in a randomized crossover design. The four sugar beverages were as follows: 100% (w/w) fructose (F100), 90% fructose+10% glucose (F90G10), 55% fructose+45% glucose (F55G45) and 100% glucose (G100). Venous blood samples were obtained at baseline and 0.5, one, two, four and six hours after ingestion.

RESULTS

The serum concentrations of TG in the F100, F90G10 and F55G45 trials were significantlyhigher than each fasting value at two and four hours, and returned to baseline at six hours, except inthe F100 trial. The concentrations at four hours and the incremental areas under the curve for thehepatic triglyceride-rich lipoprotein-triglyceride (VLDL-TG(TM)) levels in the F100 and F90G10 trialswere significantly higher and larger, respectively, than those observed in the G100 trial. Meanwhile,the concentrations of RLP-TG and apolipoprotein B-48 peaked at two hours in the G100 trial, versusfour hours in the other trials, and did not return to baseline at six hours, except in the G100 trial.At four hours, the ⊿apoB48 tended to be higher in the F100 trial than in the G100 trial.

CONCLUSIONS

The ingestion of a high-fructose-containing beverage with fat cream delays the clearance of chylomicron and its remnant derived from the intestine and enhances the secretion of triglyceride-rich lipoprotein particles from the liver, thereby inducing postprandial lipidemia, even in young healthy women.

Simultaneous ingestion of fructose and fat exacerbates postprandial exogenous lipidemia in young healthy Japanese women

AIM

To investigate the acute effects of the simultaneous ingestion of fructose and fat on postprandial lipoprotein metabolism in healthy young women.

METHODS

Nine young healthy Japanese women with a normal weight (body mass index: 18.5≤-< 25 kg/m(2)), a normal ovarian cycle and an apolipoprotein E 3/3 phenotype were enrolled as participants and studied on four occasions. At each session, the subjects ingested one of four beverages containing either glucose or fructose (0.5 g/kg body weight each) with or without OFTT cream (1 g/kg, 0.35 g/ kg as fat) in a randomized crossover design. Blood samples were collected at baseline and at 0.5, 1, 2, 4 and 6 hours after ingestion.

RESULTS

The ingestion of fructose combined with fat led to significantly higher rises in the serum triglyceride (TG), remnant-like particle (RLP)-TG, remnant lipoprotein-cholesterol (RemL-C) and apolipoprotein B-48 (apoB48) concentrations with delayed peaks compared with that observed following ingestion of the other three types of beverages. The incremental area under the curve (ΔAUC)-TG and ΔAUC-apoB48 were larger than those observed for the ingestion of fat only. The serum RLP-TG and apoB48 concentrations returned to the fasting levels (0 hours) at the end of the test (6 hours) following the ingestion of fat only; however, these concentrations did not return to the fasting levels following the intake of fructose combined with fat.

CONCLUSIONS

These findings suggest a delay in the clearance of intestinal TG-rich lipoproteins, namely chylomicron and its remnant, following the ingestion of fructose combined with fat. The simultaneous ingestion of fructose and fat markedly enhances postprandial exogenous lipidemia in young healthy Japanese women.

Exercising for metabolic control: is timing important?

Atherosclerosis-related cardiovascular disease and diabetes mellitus are leading causes of mortality in the world and both disorders are closely related to the postprandial phenomena. Regular exercise is being strongly advocated as a precious tool in easing the global burden of chronic disease. Although exercise intensity, duration and frequency are well established in current guidelines for healthy and diabetic individuals, there is still no consensus on the optimal timing of exercise in relation to the last meal. The present paper reviews the existing literature on the 'when?' of aerobic exercise for metabolic control in healthy and diabetic individuals. Effective control of postprandial phenomena might prove to be a useful tool in the prevention of chronic disease. Exercise appears to influence glycemic and triglyceridemic responses differently depending on the meal composition and time lapse from meals. In healthy individuals, fasted-state exercise favors postprandial triglyceridemic control and the insulin sensitivity related to it. However, there is a lack of data on this matter in diabetic patients. On the other hand, when postprandial glycemia is of concern, aerobic exercise works better when performed after a meal, both in healthy and in diabetic patients.