Effects of self-monitored jogging on physical fitness, blood pressure and serum lipids: a controlled study in sedentary middle-aged men

Estimating the Effect of Aerobic Exercise Training on Novel Lipid Biomarkers: A Systematic Review and Multivariate Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Aerobic exercise training (AET) prescribed as lipid management treatment positively affects the standard lipid profile and reduces cardiovascular disease (CVD) risk. Apolipoproteins, lipid and apolipoprotein ratios, and lipoprotein sub-fractions may more effectively predict CVD risk than the standard lipid profile but an AET response in these biomarkers has not been established.

OBJECTIVES

We conducted a quantitative systematic review of randomised controlled trials (RCTs) to (1) determine the effects of AET on lipoprotein sub-fractions, apolipoproteins and relevant ratios; and (2) identify study or intervention covariates associated with change in these biomarkers.

METHODS

We searched PubMed, EMBASE, all Web of Science and EBSCO health and medical online databases from inception to 31 December 2021. We included published RCTs of adult humans with ≥ 10 per group of participants; an AET intervention duration ≥ 12 weeks of at least moderate intensity (> 40% maximum oxygen consumption); and reporting pre/post measurements. Non-sedentary subjects, or those with chronic disease other than Metabolic Syndrome factors, or pregnant/lactating, as well as trials testing diet/medications, or resistance/isometric/unconventional training interventions, were excluded.

RESULTS

Fifty-seven RCTs totalling 3194 participants were analysed. Multivariate meta-analysis showed AET significantly raised antiatherogenic apolipoproteins and lipoprotein sub-fractions (mmol/L mean difference (MD) 0.047 (95% confidence interval (CI) 0.011, 0.082), P = .01); lowered atherogenic apoliproteins and lipoprotein sub-fractions (mmol/L MD - 0.08 (95% CI - 0.161, 0.0003), P = .05); and improved atherogenic lipid ratios (MD - 0.201 (95% CI - 0.291, - 0.111), P < .0001). Multivariate meta-regression showed intervention variables contributed to change in lipid, sub-fraction, and apoliprotein ratios.

CONCLUSION

Aerobic exercise training positively impacts atherogenic lipid and apolipoprotein ratios, alipoproteins, and lipoprotein sub-fractions; and antiatherogenic apolipoproteins and lipoprotein sub-fractions. Cardiovascular disease risk predicted by these biomarkers may be lowered when AET is prescribed as treatment or prevention.

PROSPERO ID

CRD42020151925.

Are home-based exercises effective to reduce blood pressure in hypertensive adults? A systematic review

Sedentarism and chronic non-communicable diseases have been a worldwide health problem that is drastically exacerbated by the COVID-19 pandemic social impacts. Home-based exercises are widely encouraged during social isolation to counterbalance the physical inactive impacts. Although, in the context of hypertension, are home-based exercises effective in blood pressure controlling? Our objective is to conduct a systematic review of high-quality controlled trials comparing the possible effects of different types of home-based exercises in hypertensive patients. The literature search was carried out in three scientific databases: Medline, Europe PMC, and Lilacs. Articles were included following three criteria: analyzing the effect of home-based exercise programs on blood pressure in treated and untreated hypertensive patients; exercises must perform at home and on the frequency, intensity, time, and type (FITT) principle, and the articles were published in English. From the qualitative analysis of 27 original trials screened through 451 identified studies, the main results are the following: 1) both endurance, isometric strength, and respiratory home-based exercise programs were efficient to decrease blood pressure in hypertensive patients; 2) differences in methodological approaches regarding FITT components, distinct blood pressure values at baseline and specific underlying mechanisms must be considered as a potential bias of each home-based interventions. In conclusion, endurance, isometric strength, and breathing home-based programs seems to be effective to reduce blood pressure in hypertensive patients. However, further randomized controlled trials and mechanistic studies must be performing to guide evidence-based recommendations of home-based exercises as antihypertensive therapy.

Running to Lower Resting Blood Pressure: A Systematic Review and Meta-analysis

BACKGROUND

According to previous epidemiological studies, there are pros and cons for the relationship between running regularly and changes in resting blood pressure (RBP), and the changes may depend on the form of exercise.

OBJECTIVE

The aims of the current systematic review were to summarize the effects of running regularly on RBP and to investigate the most efficacious form of running in reducing RBP for this purpose.

METHODS

The inclusion criteria were: randomized controlled trials, involving healthy adults or adults with hypertension, the exercise group only performed regular running and the control group did not exercise, and the study reported the mean resting systolic blood pressure (RSBP) and/or diastolic blood pressure (RDBP). The mean difference (MD) in RBP in each trial was defined as follows: (mean value at post-intervention in the exercise group - mean value at baseline in the exercise group) - (mean value at post-intervention in the control group - mean value at baseline in the control group) and was calculated. The weighted MD (WMD) was defined as the synthesis of all MD. A linear meta-regression analysis, exercise intensity [the percentage of maximum heart rate] (%) and total exercise time throughout the intervention (hours) were selected as explanatory variables and the MD in RBP served as the objective variable.

RESULTS

Twenty-two trials (736 subjects) were analyzed. When trials were limited to those involving healthy subjects, the WMD in RBP decreased significantly [RSBP: - 4.2 mmHg (95% confidence intervals (95% CI) - 5.9 to - 2.4); RDBP: - 2.7 mmHg (95% CI - 4.2 to - 1.1)] and did not contain significant heterogeneity (RSBP: P = 0.67, I² = 0.0%; DBP: P = 0.38, I² = 7.2%). When trials were limited to those involving subjects with hypertension, the WMD in RBP decreased significantly [RSBP: - 5.6 mmHg (95% CI - 9.1 to - 2.1); RDBP: - 5.2 mmHg (95% CI - 9.0 to - 1.4)] but contained significant heterogeneity (RSBP: P = 0.01, I² = 62.2%; DBP: P < 0.01, I² = 87.7) and a meta-regression analysis showed that the percentage of maximum heart rate was significantly associated with the WMD in RSBP [slope: 0.56 (95% CI 0.21 to 0.92), intercept: - 48.76 (95% CI - 76.30 to - 21.22), R² = 0.88] and RDBP [slope: 0.45 (95% CI 0.01 to 0.87), intercept: - 38.06 (95% CI - 72.30 to - 4.08), R² = 0.41]. When trials were limited to those involving subjects with hypertension and a mean age ≥ 40 years, a meta-regression analysis showed that total exercise time throughout the intervention was significantly associated with the WMD in RDBP [slope: 0.82 (95% CI 0.54 to 1.09), intercept: - 22.90 (95% CI - 29.04 to - 16.77), R² = 0.99].

CONCLUSIONS

Running regularly decreases RBP, but the changes in subjects with hypertension may differ depending on exercise intensity or total exercise time. Therefore, running regularly at moderate intensity and at a restrained volume is recommended to lower RBP in subjects with hypertension.

A Randomized Study of a Strength Training Program to Prevent Injuries in Runners of the New York City Marathon

BACKGROUND

Lower extremity overuse injuries are common among runners, especially first-time marathoners. Hip abductor and quadriceps strengthening is often recommended to reduce running-related injuries.

HYPOTHESIS

A 12-week strength training program would decrease the rate of overuse injuries resulting in marathon noncompletion and improve race finishing time.

STUDY DESIGN

Randomized trial.

LEVEL OF EVIDENCE

Level 2.

METHODS

Twelve weeks before the New York City Marathon, first-time marathon runners age 18 years and older were randomized into a strength training group or an observation group. The strength training group was instructed to perform a 10-minute program 3 times weekly using written and video instruction. This program targeted the quadriceps, hip abductor, and core muscle groups. Injuries were self-reported through biweekly surveys, with major injuries being those that resulted in marathon noncompletion and minor injuries being those that impaired training or race performance.

RESULTS

A total of 720 runners were enrolled (mean age, 35.9 ± 9.4 years; 69.4% female), of whom 583 runners started the marathon and 579 completed it. The incidence of major injury was 8.9% and minor injury was 48.5%. Fifty two of 64 major injuries were overuse, of which 20 were bone stress injuries. The incidence of overuse injury resulting in marathon noncompletion was 7.1% in the strength training group and 7.3% in the observation group (risk ratio, 0.97; 95% CI, 0.57-1.63; P = 0.90). The mean finishing time was 5 hours 1 ± 60 minutes in the strength training group and 4 hours 58 ± 55 minutes in the observation group (P = 0.35).

CONCLUSION

There is a high prevalence of injury among first-time marathon runners, but this self-directed strength training program did not decrease overuse injury incidence resulting in marathon noncompletion.

CLINICAL RELEVANCE

Prevention strategies such as strength training need to be developed and evaluated through clinical trials to reduce the high prevalence of overuse injuries in runners, especially for high-risk populations such as first-time marathon runners.

Effects of Exercise on the Resting Heart Rate: A Systematic Review and Meta-Analysis of Interventional Studies

Resting heart rate (RHR) is positively related with mortality. Regular exercise causes a reduction in RHR. The aim of the systematic review was to assess whether regular exercise or sports have an impact on the RHR in healthy subjects by taking different types of sports into account. A systematic literature research was conducted in six databases for the identification of controlled trials dealing with the effects of exercise or sports on the RHR in healthy subjects was performed. The studies were summarized by meta-analyses. The literature search analyzed 191 studies presenting 215 samples fitting the eligibility criteria. 121 trials examined the effects of endurance training, 43 strength training, 15 combined endurance and strength training, 5 additional school sport programs. 21 yoga, 5 tai chi, 3 qigong, and 2 unspecified types of sports. All types of sports decreased the RHR. However, only endurance training and yoga significantly decreased the RHR in both sexes. The exercise-induced decreases of RHR were positively related with the pre-interventional RHR and negatively with the average age of the participants. From this, we can conclude that exercise-especially endurance training and yoga-decreases RHR. This effect may contribute to a reduction in all-cause mortality due to regular exercise or sports.

Meta-Analyses of the Effects of Habitual Running on Indices of Health in Physically Inactive Adults

Background

In order to implement running to promote physical activity, it is essential to quantify the extent to which running improves health.

Objective

The aim was to summarise the literature on the effects of endurance running on biomedical indices of health in physically inactive adults.

Data Sources

Electronic searches were conducted in October 2014 on PubMed, Embase, CINAHL, SPORTDiscus, PEDro, the Cochrane Library and LILACS, with no limits of date and language of publication.

Study Selection

Randomised controlled trials (with a minimum of 8 weeks of running training) that included physically inactive but healthy adults (18–65 years) were selected. The studies needed to compare intervention (i.e. endurance running) and control (i.e. no intervention) groups.

Study Appraisal and Synthesis Methods

Two authors evaluated study eligibility, extracted data, and assessed risk of bias; a third author resolved any uncertainties. Random-effects meta-analyses were performed to summarise the estimates for length of training and sex. A dose-response analysis was performed with random-effects meta-regression in order to investigate the relationship between running characteristics and effect sizes.

Results

After screening 22,380 records, 49 articles were included, of which 35 were used to combine data on ten biomedical indices of health. On average the running programs were composed of 3.7 ± 0.9 sessions/week, 2.3 ± 1.0 h/week, 14.4 ± 5.4 km/week, at 60–90 % of the maximum heart rate, and lasted 21.5 ± 16.8 weeks. After 1 year of training, running was effective in reducing body mass by 3.3 kg [95 % confidence interval (CI) 4.1–2.5], body fat by 2.7 % (95 % CI 5.1–0.2), resting heart rate by 6.7 min⁻¹ (95 % CI 10.3–3.0) and triglycerides by 16.9 mg dl⁻¹ (95 % CI 28.1–5.6). Also, running significantly increased maximal oxygen uptake (VO_2max) by 7.1 ml min⁻¹ kg⁻¹ (95 % CI 5.0–9.1) and high-density lipoprotein (HDL) cholesterol by 3.3 mg dl⁻¹ (95 % CI 1.2–5.4). No significant effect was found for lean body mass, body mass index, total cholesterol and low-density lipoprotein cholesterol after 1 year of training. In the dose-response analysis, larger effect sizes were found for longer length of training.

Limitations

It was only possible to combine the data of ten out the 161 outcome measures identified. Lack of information on training characteristics precluded a multivariate model in the dose-response analysis.

Conclusions

Endurance running was effective in providing substantial beneficial effects on body mass, body fat, resting heart rate, VO_2max, triglycerides and HDL cholesterol in physically inactive adults. The longer the length of training, the larger the achieved health benefits. Clinicians and health authorities can use this information to advise individuals to run, and to support policies towards investing in running programs.

Electronic supplementary material

The online version of this article (doi:10.1007/s40279-015-0359-y) contains supplementary material, which is available to authorized users.

Exercise training for patients with cardiovascular disease

This review surveys effort training, a validated and recommended therapy, in patients with atheromatous cardiovascular disease. This true therapy reduces mortality by 25-35%, reduces clinical manifestations and complications (rhythm problems, thrombosis) and improves physical capacity, reintegration and quality of life. The effects are essentially linked to improved metabolic performance of muscles and reduced endothelial dysfunction, insulin resistance and neurohormonal abnormalities. Training also has an impact on the evolution of major risk factors, especially diabetes and arterial hypertension. The risks are limited as long as the contraindications are respected and the programmes supervised. The indications (stable angina, chronic heart failure, peripheral arterial disease) should be described more precisely by taking into account functional criteria: physical deconditioning, exclusion, compliance, mood swings, and seriousness of risk factors. The training programme should be tailor made and based on evaluation of the patient's adaptation to effort, in terms of frequency, intensity and duration of the exercises. Various types of exercise include overall or segmental physical training; concentric, eccentric, even isokinetic muscle contraction exercises; and proprioceptive rehabilitation. However, knowledge is lacking about the molecular mechanisms of the effects of training, the most effective intensity of effort, and strategies to develop physical activity in this ever-growing population for both primary and secondary prevention.

Evidence for prescribing exercise as therapy in chronic disease

Considerable knowledge has accumulated in recent decades concerning the significance of physical activity in the treatment of a number of diseases, including diseases that do not primarily manifest as disorders of the locomotive apparatus. In this review we present the evidence for prescribing exercise therapy in the treatment of metabolic syndrome-related disorders (insulin resistance, type 2 diabetes, dyslipidemia, hypertension, obesity), heart and pulmonary diseases (chronic obstructive pulmonary disease, coronary heart disease, chronic heart failure, intermittent claudication), muscle, bone and joint diseases (osteoarthritis, rheumatoid arthritis, osteoporosis, fibromyalgia, chronic fatigue syndrome) and cancer, depression, asthma and type 1 diabetes. For each disease, we review the effect of exercise therapy on disease pathogenesis, on symptoms specific to the diagnosis, on physical fitness or strength and on quality of life. The possible mechanisms of action are briefly examined and the principles for prescribing exercise therapy are discussed, focusing on the type and amount of exercise and possible contraindications.

Lifestyle interventions to reduce raised blood pressure: a systematic review of randomized controlled trials

PURPOSE

To quantify effectiveness of lifestyle interventions for hypertension.

DATA SOURCES

Electronic bibliographic databases from 1998 onwards, existing guidelines, systematic reviews.

STUDY SELECTION AND DATA ABSTRACTION

We included randomized, controlled trials with at least 8 weeks' follow-up, comparing lifestyle with control interventions, enrolling adults with blood pressure at least 140/85 mmHg. Primary outcome measures were systolic and diastolic blood pressure. Two independent reviewers selected trials and abstracted data; differences were resolved by discussion.

RESULTS

We categorized trials by type of intervention and used random effects meta-analysis to combine mean differences between endpoint blood pressure in treatment and control groups in 105 trials randomizing 6805 participants. Robust statistically significant effects were found for improved diet, aerobic exercise, alcohol and sodium restriction, and fish oil supplements: mean reductions in systolic blood pressure of 5.0 mmHg [95% confidence interval (CI): 3.1-7.0], 4.6 mmHg (95% CI: 2.0-7.1), 3.8 mmHg (95% CI: 1.4-6.1), 3.6 mmHg (95% CI: 2.5-4.6) and 2.3 mmHg (95% CI: 0.2-4.3), respectively, with corresponding reductions in diastolic blood pressure. Relaxation significantly reduced blood pressure only when compared with non-intervention controls. We found no robust evidence of any important effect on blood pressure of potassium, magnesium or calcium supplements.

CONCLUSIONS

Patients with elevated blood pressure should follow a weight-reducing diet, take regular exercise, and restrict alcohol and salt intake. Available evidence does not support relaxation therapies, calcium, magnesium or potassium supplements to reduce blood pressure.

Aerobic exercise and lipids and lipoproteins in men: a meta-analysis of randomized controlled trials

BACKGROUND: Aerobic exercise is recommended for improving lipoprotein and lipid levels which at less than their optimal levels are risk factors for cardiovascular disease. Evidence seems lacking for the effectiveness of exercise in reducing these levels, possibly due to small sizes in studies. We concluded a meta-analysis of the studies to examine the effects of aerobic exercise on lipids and lipoproteins in adult men. METHODS: Studies were retrieved via computerized literature searches, cross-referencing from retrieved articles, hand-searching, and expert review of our reference list. Inclusion criteria were randomized controlled trials, aerobic exercise ≥8 weeks, adult men ≥18 years of age, studies published in journal, dissertation, or master's thesis format, studies published in the English-language between January 1, 1955 and January 1, 2003, and assessment of one or more of the following lipids and lipoproteins: total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDLC), and triglycerides (TG). All coding was conducted by both authors, independent of each other. Discrepancies were resolved by consensus. RESULTS: Forty-nine randomized controlled trials representing up to 67 outcomes from 2,990 men (1,741 exercise, 1,249 control) were pooled for analysis. Using random-effects modeling, statistically significant improvements were observed for TC, HDL-C and TG, and a trend for decreases was observed for LDL-C. Changes were equivalent to improvements of 2% for TC and HDL-C, 3% of LDL-C, and 9% for TG. CONCLUSIONS: Aerobic exercise reduces TC and TG and increases HDL-C in men 18 years of age and older.

Effects of endurance training on blood pressure, blood pressure-regulating mechanisms, and cardiovascular risk factors

Previous meta-analyses of randomized controlled trials on the effects of chronic dynamic aerobic endurance training on blood pressure reported on resting blood pressure only. Our aim was to perform a comprehensive meta-analysis including resting and ambulatory blood pressure, blood pressure-regulating mechanisms, and concomitant cardiovascular risk factors. Inclusion criteria of studies were: random allocation to intervention and control; endurance training as the sole intervention; inclusion of healthy sedentary normotensive or hypertensive adults; intervention duration of > or =4 weeks; availability of systolic or diastolic blood pressure; and publication in a peer-reviewed journal up to December 2003. The meta-analysis involved 72 trials, 105 study groups, and 3936 participants. After weighting for the number of trained participants and using a random-effects model, training induced significant net reductions of resting and daytime ambulatory blood pressure of, respectively, 3.0/2.4 mm Hg (P<0.001) and 3.3/3.5 mm Hg (P<0.01). The reduction of resting blood pressure was more pronounced in the 30 hypertensive study groups (-6.9/-4.9) than in the others (-1.9/-1.6; P<0.001 for all). Systemic vascular resistance decreased by 7.1% (P<0.05), plasma norepinephrine by 29% (P<0.001), and plasma renin activity by 20% (P<0.05). Body weight decreased by 1.2 kg (P<0.001), waist circumference by 2.8 cm (P<0.001), percent body fat by 1.4% (P<0.001), and the homeostasis model assessment index of insulin resistance by 0.31 U (P<0.01); HDL cholesterol increased by 0.032 mmol/L(-1) (P<0.05). In conclusion, aerobic endurance training decreases blood pressure through a reduction of vascular resistance, in which the sympathetic nervous system and the renin-angiotensin system appear to be involved, and favorably affects concomitant cardiovascular risk factors.

Physical activity and stroke risk

Stroke represents a leading cause of morbidity and mortality especially among the elderly people, and therefore the need for effective preventive strategies is imperative. The value of physical activity for stroke prevention is not as well established as for other cardiovascular diseases. Despite some conflicting results, the majority of published studies have demonstrated a negative association between physical activity and stroke risk. In this article, we provide a concise overview of the epidemiological studies that investigate this association as well as a comprehensive analysis of the most relevant underlying pathophysiological mechanisms.

Changes in cardiorespiratory fitness and coronary heart disease risk factors following 24 wk of moderate- or high-intensity exercise of equal energy cost

This study was designed to investigate the effect of exercise intensity on cardiorespiratory fitness and coronary heart disease risk factors. Maximum oxygen consumption (Vo(2 max)), lipid, lipoprotein, and fibrinogen concentrations were measured in 64 previously sedentary men before random allocation to a nonexercise control group, a moderate-intensity exercise group (three 400-kcal sessions per week at 60% of Vo(2 max)), or a high-intensity exercise group (three 400-kcal sessions per week at 80% of Vo(2 max)). Subjects were instructed to maintain their normal dietary habits, and training heart rates were represcribed after monthly fitness tests. Forty-two men finished the study. After 24 wk, Vo(2 max) increased by 0.38 +/- 0.14 l/min in the moderate-intensity group and by 0.55 +/- 0.27 l/min in the high-intensity group. Repeated-measures analysis of variance identified a significant interaction between monthly Vo(2 max) score and exercise group (F = 3.37, P < 0.05), indicating that Vo(2 max) responded differently to moderate- and high-intensity exercise. Trend analysis showed that total cholesterol, low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, and fibrinogen concentrations changed favorably across control, moderate-intensity, and high-intensity groups. However, significant changes in total cholesterol (-0.55 +/- 0.81 mmol/l), low-density lipoprotein cholesterol (-0.52 +/- 0.80 mmol/l), and non-high-density lipoprotein cholesterol (-0.54 +/- 0.86 mmol/l) were only observed in the high-intensity group (all P < 0.05 vs. controls). These data suggest that high-intensity training is more effective in improving cardiorespiratory fitness than moderate-intensity training of equal energy cost. These data also suggest that changes in coronary heart disease risk factors are influenced by exercise intensity.

Body mass index is a good predictor of hypertension and hyperlipidemia in a rural Japanese population

OBJECTIVE

The association between body mass index (BMI) and cardiovascular risk factors, widely recognized in Western populations, was evaluated on subjects living in a rural Japanese area.

DESIGN

A cross-sectional survey.

SUBJECTS

A total of 16 871 subjects aged 40-59 y, from a rural area in Japan, participated in an annual health examination. All of the subjects were required to answer six items in a questionnaire on health behavior and provide blood samples.

MEASUREMENTS

Quetelet's index, blood pressure, total cholesterol, high-density lipoprotein cholesterol, health practices on exercise, drinking and smoking.

RESULTS

The mean BMI in the population was 23.1+/-2.9. After adjustment for sex, age and six health habits, the BMI was found to be significantly associated with blood pressure and the serum lipid levels by multivariate logistic regression analysis. The adjusted odds ratio for hypertension (> or =140/90 mmHg) against the lowest quartiles of BMI (separated by 20, 25 and 28) were 1.6, 2.8 and 5.2, respectively. The adjusted odds ratio for hypercholesterolemia (> or =240 mg/dl) against the lowest quartiles of BMI were 2.1, 3.3 and 4.6, respectively.

CONCLUSION

There was a significant relationship between the BMI and cardiovascular risk factors in a rural Japanese population. This association could be extended to lower BMI levels than those in Western populations.

Exercise characteristics and the blood pressure response to dynamic physical training

PURPOSE

The purpose of this study was to assess the influence of the characteristics of the exercise program, particularly exercise intensity, on the blood pressure response to dynamic physical training in otherwise healthy normotensive and hypertensive subjects.

METHODS

This study is a meta-analysis of randomized controlled intervention trials and a description of studies in which different training regimens have been compared.

RESULTS

The weighted net reduction of blood pressure in response to dynamic physical training averaged 3.4/2.4 mm Hg (P < 0.001). Interstudy differences in the changes in pressure were not related to weekly frequency, time per session, or exercise intensity, which ranged from approximately 45--85%; these three characteristics combined explained less than 5% of the variance of the blood pressure response. The response of diastolic blood pressure was not different according to training intensity in studies that randomized patients to training programs with different intensities. Some studies reported a greater reduction of systolic blood pressure when intensity was about 40% than when participants exercised at about 70%, but this finding was not consistent, neither within nor between studies.

CONCLUSION

Training from three to five times per week during 30--60 min per session at an intensity of about 40--50% of net maximal exercise performance appears to be effective with regard to blood pressure reduction. The evidence that higher intensity exercise would be less effective is at present inconsistent.

Aerobic exercise and resting blood pressure: a meta-analytic review of randomized, controlled trials

In this study the authors used the meta-analytic approach to examine the effects of aerobic exercise on resting systolic and diastolic blood pressure in adults. Forty-seven clinical trials representing a total of 72 effect sizes in 2543 subjects (1653 exercise, 890 control) met the criteria for inclusion. Statistically significant exercise-minus-control decreases were found for changes in resting systolic and diastolic blood pressure in both hypertensive (systolic, -6 mm Hg, 95% CI, -8 to -3; diastolic, -5 mm Hg, 95% CI, -7 to -3) and normotensive (systolic, -2 mm Hg, 95% CI, -3 to -1; diastolic, -1 mm Hg, 95% CI, -2 to -1) groups. The differences between groups were statistically significant (systolic, p=0.008; diastolic, p=0.000). Relative decreases were approximately 4% (systolic) and 5% (diastolic) in hypertensives, and 2% (systolic) and 1% (diastolic) in normotensives. It was concluded that aerobic exercise reduces resting systolic and diastolic blood pressure in adults. (c) 2001 by CHF, Inc.

Factor XIIa and triacylglycerol rich lipoproteins: responses to exercise intervention

OBJECTIVES

(a) To determine if factor XIIa (FXIIa) would be sensitive to change from exercise intervention in a group of previously sedentary/low active middle aged men and women; (b) to investigate further the previously reported relation between FXIIa and triacylglycerol (TAG) rich lipoproteins.

METHODS

Thirty seven men (mean (SD) age 57 (7) years) and 60 women (mean age 54 (7) years) completed the study. Before the intervention, these subjects were randomly allocated to a group of walkers (n = 81) or controls (n = 16). Before and after an 18 week walking intervention, fasted blood samples were collected and analysed for FXIIa, TAG, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), and apolipoprotein (apo) B.

RESULTS

Kruskal-Wallis analysis of data obtained before the intervention showed no significant differences (p>0.4) between the walking and control groups for age, height, body mass, gender, FXIIa, TAG, TC, HDL-C, or apo B, although the women did show significantly lower levels of TAG (p<0.04) and higher HDL-C (p<0.0001) than the men. General linear model analysis of data obtained after the intervention, using the baseline value as a covariate, showed significant reductions (p<0.0001) in FXIIa for the walkers compared with the controls. Pearson product-moment correlations also showed significant relations between the concentrations of FXIIa and TAG, TC, LDL-C, and apo B.

CONCLUSIONS

The findings of this study suggest that FXIIa is sensitive to change from exercise intervention and support previous research showing an association between the concentrations of FXIIa and TAG rich lipoproteins.

Physical activity in the prevention and treatment of hypertension in the obese

Physical activity in the prevention and treatment of hypertension in the obese.

PURPOSE

The purpose of this paper was to assess the value of physical exercise in the prevention and treatment of hypertension with particular attention to possible interactions with relative weight.

METHODS

We describe epidemiological studies and report meta-analyses of randomized intervention trials, i.e., randomized controlled trials on dynamic physical training and randomized comparative trials of exercise and diet.

RESULTS

Epidemiological studies show an inverse relationship between physical activity or fitness and the incidence of hypertension, which was either independent of body size or more pronounced in the overweight. The weighted net reduction of blood pressure in response to dynamic physical training averages 3.4/2.4 mm Hg (P < 0.001), which appears to be unrelated to the initial body mass index (BMI) and to its training-induced changes. Exercise is less effective than diet in lowering blood pressure (P < 0.02), and adding exercise to diet does not appear to further reduce blood pressure. Future studies should observe scientific criteria more strictly, address the truly obese (BMI > or = 30 kg x m(-2)) and attempt to resolve the blood pressure lowering mechanisms.

CONCLUSION

Physical activity contributes to the control of blood pressure in overweight as well as in lean subjects.

The effect of two different 18-week walking programmes on aerobic fitness, selected blood lipids and factor XIIa

Forty-nine previously sedentary or low active individuals aged 40-71 years were allocated to three groups. The long walking group participated in an 18-week walking programme which consisted of walks lasting 20-40 min; the repetitive short walking group completed walks of between 10 and 15 min, up to three times a day, with no less than 120 min between each walk; and the control group maintained their low level of activity. Both walking programmes began at a prescribed 60 min x week(-1), which increased steadily up to 200 min x week(-1) by week 12. During the study, the long walking group walked for an estimated 2514 min (139 min x week(-1)), expending an estimated 67.5 MJ (3.72 MJ x week(-1)) at an estimated 73% of their age-predicted maximum heart rate and 68% of their estimated VO2max. The repetitive short walking group walked for an estimated 2476 min (135 min x week(-1)), expending an estimated 58.5 MJ (3.17 MJ x week(-1)) at an estimated 71% of their age-predicted maximum heart rate and 65% of their estimated VO2max. The results showed a statistically significant reduction in heart rate during a standardized step test (pre- vs post-intervention) in both walking groups, indicating an improvement in aerobic fitness, although the control group showed a higher average heart rate during the post-intervention test, indicating reduced fitness. When compared with the male subjects pre-intervention, the females possessed more favourable levels of high-density lipoprotein (HDL) cholesterol (P< 0.001), apolipoprotein (apo) AI (P < 0.001) and ratios of total cholesterol:HDL cholesterol (P< 0.02) and low-density lipoprotein (LDL) cholesterol: HDL cholesterol (P< 0.02). Compared with the controls post-intervention, the walking groups showed no statistically significant changes in total cholesterol, LDL cholesterol, HDL cholesterol, apo AI, apo AII, apo B, or the ratios of total cholesterol: HDL cholesterol, LDL cholesterol: HDL cholesterol, apo AI: apo B or apo AI: apo AII (P > 0.05). Relative to the walking groups, factor XIIa increased in the control group (P < 0.05). We conclude that, although both walking programmes appeared to improve aerobic fitness, there was no evidence of improvements in the blood lipids or associated apolipoproteins of the walking groups. Further analysis indicated that this apparent lack of change may have been related to the subjects' relatively good pre-intervention blood lipid profiles, which restricted the potential for change. The implications of the observed changes in the coagulation/fibrinolytic factors remain unclear.

Physiological effects of downhill skiing at moderate altitude in untrained middle-aged men

To evaluate whether occasional strong physical activity at moderate altitude for several consecutive days is acceptable in untrained middle-aged people, 10 men (age range, 46-59 years) underwent physical examinations before (control day, D0), during (D1-D8), and after 1 wk of leisure alpine skiing. With respect to D0, the resting concentration of plasma noradrenaline (NOR) increased transiently (p < 0.01) on D2 and then increased to a maximal value from D6-D8 (p < 0.01). There was no significant change in the concentration of adrenaline. Although maximal voluntary contraction of knee extensors diminished on D3 (P < 0.05), that of the digit flexors did not change. Heart rate (HR) and blood pressure at rest in the evening were always higher than control values except on D4 (forced rest). After the stay, there was a reduction in sympathetic activity. This was reflected by a return of NOR to its control value, a decrease in resting HR (64.2 [11.4] beats per minute [bpm]: control: 71.1 [10.1] bpm, P < 0.02), a tendency for triglyceride and insulin resistance to decrease, and a significant increase in alipoprotein A1/alipoprotein A2 (P < 0.01). Our results show that despite signs of fatigue on D3, the effects of physical activity that is relatively intense (HR > 70% maximal HR) together with mild hypoxia are well tolerated by untrained middle-aged men and that the controlled practice of downhill skiing may be accepted into a program to lower cardiovascular risk factors.

Relationships between change in aerobic fitness and changes in blood pressure and plasma lipids in men and women: the "Adelaide 1000" 4-year follow up

The aim was to assess relationships between increased aerobic fitness sustained over 4 years, and changes in blood pressure (SBP and DBP) and lipids. Measurements were made of BP, lipids, weight, and fitness in 1000 middle-aged men and women entering a fitness programme, and were repeated 2 and 4 years later. The 342 men and women selected for this 4-year follow-up were either consistent fitness "gainers" (improved by > 5%) or "non-gainers" (improved by < or = 5%) at 2 and 4 year stages. For men, comparisons of these groups and multiple regression analyses failed to show significant relationships between changes in fitness and risk factors over the 4 year period. For women, "gainers" improved more than "non-gainers" in SBP (by 4 mmHg, p < 0.03), HDL/cholesterol ratio (by 0.01 mmol l-1, p < 0.0001), and triglycerides (by 0.02 mmol l-1, p < 0.05); regression analyses resulted in a significant relationship between changes in fitness and SBP (B = 0.012, p < 0.05). The study gave weak support to the existence of causal relationships between aerobic fitness and CHD risk factors for women, and no support for men.