Reduced diabetic, hypertensive, and cholesterol medication use with walking

The Trends of Medical Care Expenditure with Adjustment of Lifestyle Habits and Medication; 10-Year Retrospective Follow-Up Study

In Japan, the prevention of lifestyle-related diseases is the most important issue for the optimization of medical expenditure. This study aimed to analyze the impact of lifestyle and medication status on medical expenditure. Health checkup data and medical expenditure records of a retrospective cohort of 1463 people aged between 40 and 65 years old who underwent specific health checks at least three times between 2008 and 2017 were analyzed. Regression analysis was performed with medical expenditure as the dependent variable and age, gender, waist ratio, medication status, and lifestyle habits as independent variables using a Tobit model. Focusing on the factors that increase medical expenditure, the regression coefficients of age, medication status, weight gain of 10 kg or more since the age of 20, and walking more than 1 h per day were 0.048 (95% CI 0.04 to 0.06), 1.020 (95% CI 0.88 to 1.16), 0.210 (95% CI 0.06 to 0.36), and -0.208 (95% CI -0.35 to -0.07), respectively. The estimate of 5-year cumulative medical expenditure showed that those with walking habits without medication had the lowest medical expenditure. The result of this study suggests that walking more than 1 h a day may lower health expenditure in the general population.

Motoric cognitive risk syndrome: Integration of two early harbingers of dementia in older adults

Dementia is characterized by a long preclinical phase that may last years to decades before the onset of mild cognitive impairment. Slow gait speed and subjective memory complaint commonly co-occur during this preclinical phase, and each is a strong independent predictor of cognitive decline and dementia. Motoric cognitive risk (MCR) syndrome is a pre-dementia syndrome that combines these two early harbingers of dementia. The risk of cognitive decline or dementia is stronger for MCR than for either slow gait speed or subjective memory complaint alone. Slow gait speed and subjective memory complaint have several common risk factors: cardiovascular disease, diabetes mellitus, abnormal cortisol profiles, low vitamin D levels, brain atrophy with decreased hippocampal volume, and increased deposition of beta-amyloid in the brain. The underlying pathogenesis of MCR remains poorly understood. Metabolomics and proteomics have great potential to provide new insights into biological pathways involved in MCR during the long preclinical phase preceding dementia.

Interventions to promote cardiometabolic health and slow cardiovascular ageing

Cardiovascular ageing and the atherosclerotic process begin very early in life, most likely in utero. They progress over decades of exposure to suboptimal or abnormal metabolic and hormonal risk factors, eventually culminating in very common, costly, and mostly preventable target-organ pathologies, including coronary heart disease, stroke, heart failure, aortic aneurysm, peripheral artery disease, and vascular dementia. In this Review, we discuss findings from preclinical and clinical studies showing that calorie restriction (CR), intermittent fasting, and adjusted diurnal rhythm of feeding, with adequate intake of specific macronutrients and micronutrients, are powerful interventions not only for the prevention of cardiovascular disease but also for slowing the accumulation of molecular damage leading to cardiometabolic dysfunction. Furthermore, we discuss the mechanisms through which a number of other nondietary interventions, such as regular physical activity, mindfulness-based stress-reduction exercises, and some CR-mimetic drugs that target pro-ageing pathways, can potentiate the beneficial effects of a healthy diet in promoting cardiometabolic health.

Leucine and resistance training improve hyperglycemia, white adipose tissue loss, and inflammatory parameters in an experimental model of type 1 diabetes

BACKGROUND

Loss of white adipose tissue (WAT), associated with type 1 diabetes (DM1), contributes to increased chronic systemic inflammation.

AIM

The aim of this study was to investigate the effects of leucine supplementation and resistance training (RT) in attenuating WAT loss and improving inflammatory parameters and glucose metabolism in DM1 rats.

METHODS

Thirty-two male Wistar rats were distributed into four groups: DA (sedentary and supplemented with non-essential amino acids (NEAA)), DL (sedentary and supplemented with leucine), DTA (submitted to RT and supplemented with NEAA) and DTL (submitted to RT and supplemented with leucine). DM1 was induced by streptozotocin (STZ). An 8-week period of RT consisted of climbing a ladder with a progressively increased load, and supplementation was offered in the feed.

RESULTS

Glycemia, polyphagia and polydipsia were lower in DL, DTA and DTL groups compared with the DA group by approximately 20% ( p<.0001), 28% ( p=.004) and 64% ( p<.0001), respectively. Weight of total WAT and retroperitoneal adipose tissue (RPAT) were higher by approximately 21% ( p=.01) and 54% ( p=.0004), respectively, in DL, DTA and DTL groups compared with DA. However, gene expression of adiponectin and leptin in RPAT was only increased by RT (DTA and DTL) compared with DA and DL by approximately 93% ( p<.0001) and 78% ( p=.0002), respectively. Similarly, the levels of adiponectin in the serum, tissue IL-10 (RPAT) and serum IL-10 were only increased in DTA and DTL compared with DA and DL by approximately 31% ( p=.03), 45% ( p=.0009) and 35% ( p=.003), respectively.

CONCLUSIONS

Both interventions, isolated or together, reduced hyperglycemia and excessive loss of WAT, but RT was the main factor responsible for attenuating inflammation.

A Comparative Effectiveness Trial of Three Walking Self-monitoring Strategies

Walking programs improve health outcomes in adults at risk for cardiovascular disease (CVD), and self-monitoring strategies can improve adherence to such programs. The objective of this study was to determine whether a 6-month Internet-based walking program using Web-enhanced pedometers results in more weight loss than walking programs based on time or simple pedometer step count goals in adults with or at risk for CVD. This was a multisite, randomized controlled trial of 255 male veterans who were ambulatory, insufficiently active, and with body mass index (BMI) ≥28, and who reported CVD risk factors ≥1 risk factors. Participants were randomized to one of three self-monitoring strategies to increase walking: 1) time-based walking goals; 2) simple pedometer-based walking goals; and 3) Web-enhanced pedometer feedback goals with Internet-mediated feedback. All participants also attended five individual weight loss sessions with a dietitian. The main outcome measure was change in weight at 6 months (kg), and the secondary outcomes were change in accelerometer-measured physical activity (min) and change in health-related quality of life at 6 months. The 255 participants had a mean age of 56.3 yr (SD = 10.0), BMI = 36.3 (SD = 5.3), with a mean value of 5.2 (SD = 2.3) medical comorbidities. Dropouts were distributed evenly across the three groups, and 72% of participants completed the program. At 6 months, participants in the Web-enhanced pedometer arm lost significantly more weight (−1.9 kg, 95% CI, −2.7 to −1.1) than those in the time-based group (−0.7 kg, 95% CI, −1.5 to 0.0; P = 0.04) and simple pedometer group (−0.6 kg, 95% CI, −1.4 to 0.2; P = 0.02). In conclusion, Internet-enhanced pedometers result in greater weight loss in veterans than in walking programs using time-based walking goals or simple pedometers.

Expenditures of medicine use in hypertensive/diabetic elderly and physical activity and engagement in walking: cross secctional analysis of SABE Survey

BACKGROUND

The literature shows the inverse association between physical activity level (PAL) and chronic diseases that have a significant burden over health care costs. However, in upper-middle income countries and in elderly population this information are scarce.

OBJECTIVE

To describe the annual drug expenditures for the hypertensive and diabetic elderly population in Brazil and to analyze the association with PAL and engagement in walking.

METHODS

This cross sectional study is part of SABE Survey and comprised 806 hypertensive and/or diabetic elderly (≥60 years old). The annual expenditures of medicine use was estimated for all medications for hypertension and/or diabetes they were taking. The PAL was considered insufficient when moderate physical activity was <150 min/week or vigorous physical activity was < 75 min/week. Engagement in walking was considered by at least 1 day a week. All expenditures were presented through the descriptive values (in American Dollars US$) according PAL and engagement in walking. The association analysis between annual expenditures, PAL and engagement in walking were performed by multiple logistic regression models adjusted for gender, age and body mass index.

RESULTS

The average annual cost was higher in diabetic and insufficient physically activity elderly. The 1-year estimated.cost was US$ 73386,09 and 295% higher in insufficiently physically active. Older people who reported not walking had a higher risk to higher annual expenditures of medicine use (OR = 1.57, 95% CI 1.03-2.40).

CONCLUSIONS

The annual expenditures of medicine use for controlling hypertension and diabetes of Brazilian elderly were higher and inversely associated with physical activity level and engagement in walking.

Reduced total and cause-specific mortality from walking and running in diabetes

PURPOSE

This study aimed to assess the relationships of running and walking to mortality in diabetic subjects.

METHODS

We studied the mortality surveillance between January 1, 1989 and December 31, 2008, of 2160 participants of the National Walkers' and Runners' Health Studies who reported using diabetic medications at baseline. Hazard ratios (HR) and 95% confidence intervals (95% CI) were obtained from Cox proportional hazard analyses for mortality versus exercise energy expenditure (MET-hours per day, 1 MET·h ∼1-km run or a 1.5-km brisk walk).

RESULTS

Three hundred and thirty-one diabetic individuals died during a 9.8-yr average follow-up. Merely meeting the current exercise recommendations was not associated with lower all-cause mortality (P = 0.61), whereas exceeding the recommendations was associated with lower all-cause mortality (HR = 0.64, 95% CI = 0.49-0.82, P = 0.0005). Greater MET-hours per day ran or walked was associated with 40% lower risk for all chronic kidney disease-related deaths (HR = 0.60 per MET·h·d(-1), 95% CI = 0.35-0.91, P = 0.02), 31% lower risk for all sepsis-related deaths (HR = 0.69, 0.47-0.94, P = 0.01), and 31% lower risk for all pneumonia and influenza-related deaths (HR = 0.69, 95% CI = 0.45-0.97, P = 0.03). Running or walking ≥1.8 MET·h·d(-1) was associated with 57% reduction in cardiovascular disease (CVD) as an underlying cause of death and 46% lower risk for all CVD-related deaths versus <1.07 MET·h·d. All results remained significant: 1) adjusted for baseline BMI and 2) excluding all deaths within 3 yr of baseline.

CONCLUSIONS

These results suggest that 1) exercise is associated with significantly lower all-cause, CVD, chronic kidney disease, sepsis, and pneumonia, and influenza mortality in diabetic patients and 2) higher exercise standards may be warranted for diabetic patients than currently provided to the general population.

Increased cardiovascular disease mortality associated with excessive exercise in heart attack survivors

OBJECTIVE

To test whether greater exercise is associated with progressively lower mortality after a cardiac event.

PATIENTS AND METHODS

We used Cox proportional hazard analyses to examine mortality vs estimated energy expended by running or walking measured as metabolic equivalents (3.5 mL O2/kg per min per day or metabolic equivalent of task-h/d [MET-h/d]) in 2377 self-identified heart attack survivors, where 1 MET-h/d is the energy equivalent of running 1 km/d. Mortality surveillance via the National Death Index included January 1991 through December 2008.

RESULTS

A total of 526 deaths occurred during an average prospective follow-up of 10.4 years, 376 (71.5%) of which were related to cardiovascular disease (CVD) (International Statistical Classification of Diseases, 10th Revision codes I00-I99). CVD-related mortality compared with the lowest exercise group decreased by 21% for 1.07 to 1.8 MET-h/d of running or walking (P=.11), 24% for 1.8 to 3.6 MET-h/d (P=.04), 50% for 3.6 to 5.4 MET-h/d (P=.001), and 63% for 5.4 to 7.2 MET-h/d (P<.001) but decreased only 12% for ≥7.2 MET-h/d (P=.68). These data represent a 15% average risk reduction per MET-h/d for CVD-related mortality through 7.2 MET-h/d (P<.001) and a 2.6-fold risk increase above 7.2 MET-h/d (P=.009). Relative to the risk reduction at 7.2 MET-h/d, the risk for ≥7.2 MET-h/d increased 3.2-fold (P=.006) for all ischemic heart disease (IHD)-related mortalities but was not significantly increased for non-IHD-CVD, arrhythmia-related CVD, or non-CVD-related mortalities.

CONCLUSION

Running or walking decreases CVD mortality risk progressively at most levels of exercise in patients after a cardiac event, but the benefit of exercise on CVD mortality and IHD deaths is attenuated at the highest levels of exercise (running: above 7.1 km/d or walking briskly: 10.7 km/d).

Downhill walking to improve lower limb strength in healthy young adults

Walking is the most natural physical activity to maintain and improve fitness and health. Walking downhill is usefully adopted to plan training programmes to improve the strength, particularly in older adults. The present research was aimed to evaluate the influence of downhill walking on leg strength in young adult. A total of 32 females (age 26 ± 4 years; height 1.64 ± 0.05 m; body mass 57.6 ± 5.6 kg) were divided into four groups and they carried out an exercise intervention consisting of three sessions per week for 6 weeks, each lasting 30 minutes. Groups were defined at several workloads characterised by treadmill inclination (%) and walking speed (m · s(-1)): Level Walking at treadmill inclination 0% and walking speed 1.0; Uphill Walking at +20%, 0.75; Downhill Walking (DW) at -20%, 1.36; and Mixed Walking at +20%, 0.75 and -20%, 1.36 each lasting 15 minutes. Maximum voluntary contraction (MVC) developed by the Quadriceps Femoris and Endurance Time at 60% MVC were evaluated before and after experimental period. At the end of each session, Borg's scale and Visual Analogue Scale (VAS) were adopted in order to evaluate perception of rate exertion and pain. Statistical analysis showed significant only in MVC for DW in both right and left legs. Borg's scale and VAS described light activity free of pain. Present findings showed how an eccentric exercise, short lasting and at a low workload, can be useful in inducing improvements in leg strength.

Dose-response relationship of physical activity to premature and total all-cause and cardiovascular disease mortality in walkers

Purpose

To assess the dose-response relationships between cause-specific mortality and exercise energy expenditure in a prospective epidemiological cohort of walkers.

Methods

The sample consisted of the 8,436 male and 33,586 female participants of the National Walkers' Health Study. Walking energy expenditure was calculated in metabolic equivalents (METs, 1 MET = 3.5 ml O₂/kg/min), which were used to divide the cohort into four exercise categories: category 1 (≤1.07 MET-hours/d), category 2 (1.07 to 1.8 MET-hours/d), category 3 (1.8 to 3.6 MET-hours/d), and category 4 (≥3.6 MET-hours/d). Competing risk regression analyses were use to calculate the risk of mortality for categories 2, 3 and 4 relative to category 1.

Results

22.9% of the subjects were in category 1, 16.1% in category 2, 33.3% in category 3, and 27.7% in category 4. There were 2,448 deaths during the 9.6 average years of follow-up. Total mortality was 11.2% lower in category 2 (P = 0.04), 32.4% lower in category 3 (P<10⁻¹²) and 32.9% lower in category 4 (P = 10⁻¹¹) than in category 1. For underlying causes of death, the respective risk reductions for categories 2, 3 and 4 were 23.6% (P = 0.008), 35.2% (P<10⁻⁵), and 34.9% (P = 0.0001) for cardiovascular disease mortality; 27.8% (P = 0.18), 20.6% (P = 0.07), and 31.4% (P = 0.009) for ischemic heart disease mortality; and 39.4% (P = 0.18), 63.8% (P = 0.005), and 90.6% (P = 0.002) for diabetes mortality when compared to category 1. For all related mortality (i.e., underlying and contributing causes of death combined), the respective risk reductions for categories 2, 3 and 4 were 18.7% (P = 0.22), 42.5% (P = 0.001), and 57.5% (P = 0.0001) for heart failure; 9.4% (P = 0.56), 44.3% (P = 0.0004), and 33.5% (P = 0.02) for hypertensive diseases; 11.5% (P = 0.38), 41.0% (P<10⁻⁴), and 35.5% (P = 0.001) for dysrhythmias: and 23.2% (P = 0.13), 45.8% (P = 0.0002), and 41.1% (P = 0.005) for cerebrovascular diseases when compared to category 1.

Conclusions

There are substantial health benefits to exceeding the current exercise guidelines.

The relationship of walking intensity to total and cause-specific mortality. Results from the National Walkers' Health Study

PURPOSE

Test whether: 1) walking intensity predicts mortality when adjusted for walking energy expenditure, and 2) slow walking pace (≥24-minute mile) identifies subjects at substantially elevated risk for mortality.

METHODS

Hazard ratios from Cox proportional survival analyses of all-cause and cause-specific mortality vs. usual walking pace (min/mile) in 7,374 male and 31,607 female recreational walkers. Survival times were left censored for age at entry into the study. Other causes of death were treated as a competing risk for the analyses of cause-specific mortality. All analyses were adjusted for sex, education, baseline smoking, prior heart attack, aspirin use, diet, BMI, and walking energy expenditure. Deaths within one year of baseline were excluded.

RESULTS

The National Death Index identified 1968 deaths during the average 9.4-year mortality surveillance. Each additional minute per mile in walking pace was associated with an increased risk of mortality due to all causes (1.8% increase, P=10(-5)), cardiovascular diseases (2.4% increase, P=0.001, 637 deaths), ischemic heart disease (2.8% increase, P=0.003, 336 deaths), heart failure (6.5% increase, P=0.001, 36 deaths), hypertensive heart disease (6.2% increase, P=0.01, 31 deaths), diabetes (6.3% increase, P=0.004, 32 deaths), and dementia (6.6% increase, P=0.0004, 44 deaths). Those reporting a pace slower than a 24-minute mile were at increased risk for mortality due to all-causes (44.3% increased risk, P=0.0001), cardiovascular diseases (43.9% increased risk, P=0.03), and dementia (5.0-fold increased risk, P=0.0002) even though they satisfied the current exercise recommendations by walking ≥7.5 metabolic equivalent (MET)-hours per week.

CONCLUSIONS

The risk for mortality: 1) decreases in association with walking intensity, and 2) increases substantially in association for walking pace ≥24 minute mile (equivalent to <400 m during a six-minute walk test) even among subjects who exercise regularly.

Walking and running produce similar reductions in cause-specific disease mortality in hypertensives

To test prospectively in hypertensives whether moderate and vigorous exercise produces equivalent reductions in mortality, Cox-proportional hazard analyses were applied to energy expenditure (metabolic equivalents hours/d [METh/d]) in 6973 walkers and 3907 runners who used hypertensive medications at baseline. A total of 1121 died during 10.2-year follow-up: 695 cardiovascular disease (International Classification of Diseases, Tenth Revision [ICD10] I00-99; 465 underlying cause and 230 contributing cause), 124 cerebrovascular disease, 353 ischemic heart disease (ICD10 I20-25; 257 underlying and 96 contributing), 122 heart failure (ICD10 I50; 24 underlying and 98 contributing), and 260 dysrhythmias (ICD10 I46-49; 24 underlying and 236 contributing). Relative to <1.07 METh/d, running or walking 1.8 to 3.6 METh/d produced significantly lower all-cause (29% reduction; 95% confidence interval [CI], 17%-39%; P=0.0001), cardiovascular disease (34% reduction; 95% CI, 20%-46%; P=0.0001), cerebrovascular disease (55% reduction; 95% CI, 27%-73%; P=0.001), dysrhythmia (47% reduction; 95% CI, 27%-62%; P=0.0001), and heart failure mortality (51% reduction; 95% CI, 21%-70%; P=0.003), as did ≥ 3.6 METh/d with all-cause (22% reduction; 95% CI, 6%-35%; P=0.005), cardiovascular disease (36% reduction; 95% CI, 19%-50%; P=0.0002), cerebrovascular disease (47% reduction; 95% CI, 6%-71%; P=0.03), and dysrhythmia mortality (43% reduction; 95% CI, 16%-62%; P=0.004). Diabetes mellitus and chronic kidney disease mortality also decreased significantly with METh/d. All results remained significant when body mass index adjusted. Merely meeting guideline levels (1.07-1.8 METh/d) did not significantly reduced mortality. The dose-response was significantly nonlinear for all end points except diabetes mellitus, and cerebrovascular and chronic kidney disease. Results did not differ between running and walking. Thus, walking and running produce similar reductions in mortality in hypertensives.

Reduced incidence of cardiac arrhythmias in walkers and runners

Purpose

Walking is purported to reduce the risk of atrial fibrillation by 48%, whereas jogging is purported to increase its risk by 53%, suggesting a strong anti-arrhythmic benefit of walking over running. The purpose of these analyses is to compare incident self-reported physician-diagnosed cardiac arrhythmia to baseline energy expenditure (metabolic equivalent hours per day, METhr/d) from walking, running and other exercise.

Methods

Proportional hazards analysis of 14,734 walkers and 32,073 runners.

Results

There were 1,060 incident cardiac arrhythmias (412 walkers, 648 runners) during 6.2 years of follow-up. The risk for incident cardiac arrhythmias declined 4.4% per baseline METhr/d walked by the walkers, or running in the runners (P = 0.0001). Specifically, the risk declined 14.2% (hazard ratio: 0.858) for 1.8 to 3.6 METhr/d, 26.5% for 3.6 to 5.4 METhr/d, and 31.7% for ≥5.4 METhr/d, relative to <1.8 METhr/d. The risk reduction per METhr/d was significantly greater for walking than running (P<0.01), but only because walkers were at 34% greater risk than runners who fell below contemporary physical activity guideline recommendations; otherwise the walkers and runners had similar risks for cardiac arrhythmias. Cardiac arrhythmias were unrelated to walking and running intensity, and unrelated to marathon participation and performance.

Conclusions

The risk for cardiac arrhythmias was similar in walkers and runners who expended comparable METhr/d during structured exercise. We found no significant risk increase for self-reported cardiac arrhythmias associated with running distance, exercise intensity, or marathon participation. Rhythm abnormalities were based on self-report, precluding definitive categorization of the nature of the rhythm disturbance. However, even if the runners’ arrhythmias include sinus bradycardia due to running itself, there was no increase in arrhythmias with greater running distance.

Resistance training decreases serum inflammatory markers in diabetic rats

Inflammation plays an important role in the genesis and progression of diabetes. The purpose of this study was to investigate the effect of resistance training on serum levels of some inflammatory markers associated with diabetes mellitus. Twenty-four male Wistar rats (290 ± 19 g) were randomly divided into three groups: non-diabetic control (non-DC), diabetic control (DC), and diabetic trained (DT). Animals in DT group were subjected to a resistance training program with the use of a ladder (3 days/week, for 4 weeks). Body weight, serum high sensitivity C-reactive protein (hs-CRP), interleukin (IL)-6, tumor necrosis factor (TNF)-α, fasting glucose, and insulin were measured. Four weeks of resistance training decreased serum levels of TNF-α, hs-CRP, and IL-6 in diabetic rats when compared with DC animals. We conclude that resistance training with appropriate intensity, duration, and recovery between exercise bouts has marked anti-inflammatory effects on diabetic rats. This may be an efficient strategy to protect against some diabetic complications.

Walking versus running for hypertension, cholesterol, and diabetes mellitus risk reduction

OBJECTIVE

To test whether equivalent energy expenditure by moderate-intensity (eg, walking) and vigorous-intensity exercise (eg, running) provides equivalent health benefits.

APPROACH AND RESULTS

We used the National Runners' (n=33 060) and Walkers' (n=15 945) Health Study cohorts to examine the effect of differences in exercise mode and thereby exercise intensity on coronary heart disease (CHD) risk factors. Baseline expenditure (metabolic equivant hours per day [METh/d]) was compared with self-reported, physician-diagnosed incident hypertension, hypercholesterolemia, diabetes mellitus, and CHD during 6.2 years follow-up. Running significantly decreased the risks for incident hypertension by 4.2% (P<10(-7)), hypercholesterolemia by 4.3% (P<10(-14)), diabetes mellitus by 12.1% (P<10(-5)), and CHD by 4.5% per METh/d (P=0.05). The corresponding reductions for walking were 7.2% (P<10(-6)), 7.0% (P<10(-8)), 12.3% (P<10(-4)), and 9.3% (P=0.01). Relative to <1.8 METh/d, the risk reductions for 1.8 to 3.6, 3.6 to 5.4, 5.4 to 7.2, and ≥7.2 METh/d were as follows: (1) 10.1%, 17.7%, 25.1%, and 34.9% from running and 14.0%, 23.8%, 21.8%, and 38.3% from walking for hypercholesterolemia; (2) 19.7%, 19.4%, 26.8%, and 39.8% from running and 14.7%, 19.1%, 23.6%, and 13.3% from walking for hypertension; and (3) 43.5%, 44.1%, 47.7%, and 68.2% from running, and 34.1%, 44.2% and 23.6% from walking for diabetes mellitus (walking >5.4 METh/d excluded for too few cases). The risk reductions were not significantly different for running than walking for diabetes mellitus (P=0.94), hypertension (P=0.06), or CHD (P=0.26), and only marginally greater for walking than running for hypercholesterolemia (P=0.04).

CONCLUSIONS

Equivalent energy expenditures by moderate (walking) and vigorous (running) exercise produced similar risk reductions for hypertension, hypercholesterolemia, diabetes mellitus, and possibly CHD.

Workload comparison between hiking and indoor physical activity

Walking is a physical activity able to maintain and improve aerobic fitness. This activity can easily be performed in all seasons both outdoors and indoors, but when it is performed in its natural environment, the use of specific equipment is required. In particular, it has been demonstrated that the use of trekking boots (TBs) induces a larger workload than those used indoors. Because an adequate fitness level is needed to practice hiking in safety, it is useful to know the energy demand of such an activity. This research aims at defining the metabolic engagement of hiking on natural paths with specific equipment at several speeds and comparing this with indoor ones (on a treadmill). This can thence be used to define the load that better reflects the one required to walk on natural paths. The walking energy cost (joules per kilogram per meter) at several speeds (0.28, 0.56, 0.84, 1.11, and 1.39 m·s(-1))-on level natural terrain while wearing suitable footwear (TBs) and on a treadmill at various raising slopes (0, 1, 2, 3, 4%) while wearing running shoes-was measured in 14 healthy young men (age 23.9 ± 2.9 years, stature 1.75 ± 0.04 m, and body mass 72.9 ± 6.3 kg). A physiological evaluation of all the subjects was performed before energy cost measurements. The results showed that outdoors, the oxygen uptake was consistently less than the ventilatory threshold at all speeds tested and that a 3% slope on the treadmill best reflects the outdoor walking energy expenditure. These findings will prove useful to plan proper training for hiking activity or mixed (outdoors and indoors) training program.

Walking attenuates the relationships of high-meat, low-fruit dietary intake to total and regional adiposity in men and women

Vigorous physical activity (running) has been shown to attenuate the association between diet and body weight. Walking is the most popular physical activity, but is a moderate-intensity physical activity because it requires less than sixfold the energy expenditure of sitting at rest. We therefore examined whether reported distance walked per week affected the relationship of diet to BMI and circumferences of the waist, hip, and chest in 30,014 female and 7,133 male participants of the National Walkers' Health Study. Reported meat and fruit intakes served as indicators of high-risk diets for weight gain. The analyses showed that higher meat and lower fruit intake were significantly and consistently associated with greater BMI and waist circumference at all activity levels. Longer usual walking distance significantly attenuated the concordant relationships of diet with women's BMIs (P < 10(-8)), men's BMIs (P = 0.04), and women's waist (P < 10(-6)), hip (P = 0.0001), and chest circumferences (P < 10(-5)). Compared to walkers who averaged <1.5 km/day, the association of diet with adiposity in subjects who walked ≥1.5 km/day was reduced 21% in women and 31% in men for BMI; 20% in women and 27% in men for waist circumference; 19% for women's hip circumference; and 26% for women's chest circumference. Thus we conclude that diets characterized by high-meat/low-fruit intake were significantly associated with greater BMI, and this association was attenuated by moderate physical activity. The weaker results in men than women probably related to the smaller sample size, and reduced statistical power of the men.

Distance walked and run as improved metrics over time-based energy estimation in epidemiological studies and prevention; evidence from medication use

PURPOSE

The guideline physical activity levels are prescribed in terms of time, frequency, and intensity (e.g., 30 minutes brisk walking, five days a week or its energy equivalence) and assume that different activities may be combined to meet targeted goals (exchangeability premise). Habitual runners and walkers may quantify exercise in terms of distance (km/day), and for them, the relationship between activity dose and health benefits may be better assessed in terms of distance rather than time. Analyses were therefore performed to test: 1) whether time-based or distance-based estimates of energy expenditure provide the best metric for relating running and walking to hypertensive, high cholesterol, and diabetes medication use (conditions known to be diminished by exercise), and 2) the exchangeability premise.

METHODS

Logistic regression analyses of medication use (dependent variable) vs. metabolic equivalent hours per day (METhr/d) of running, walking and other exercise (independent variables) using cross-sectional data from the National Runners' (17,201 male, 16,173 female) and Walkers' Health Studies (3,434 male, 12,384 female).

RESULTS

Estimated METhr/d of running and walking activity were 38% and 31% greater, respectively, when calculated from self-reported time than distance in men, and 43% and 37% greater in women, respectively. Percent reductions in the odds for hypertension and high cholesterol medication use per METhr/d run or per METhr/d walked were ≥ 2-fold greater when estimated from reported distance (km/wk) than from time (hr/wk). The per METhr/d odds reduction was significantly greater for the distance- than the time-based estimate for hypertension (runners: P<10(-5) for males and P=0.003 for females; walkers: P=0.03 for males and P<10(-4) for females), high cholesterol medication use in runners (P<10(-4) for males and P=0.02 for females) and male walkers (P=0.01 for males and P=0.08 for females) and for diabetes medication use in male runners (P<10(-3)).

CONCLUSIONS

Although causality between greater exercise and lower prevalence of hypertension, high cholesterol and diabetes cannot be inferred from these cross-sectional data, the results do suggest that distance-based estimates of METhr/d run or walked provide superior metrics for epidemiological analyses to their traditional time-based estimates.

Dose-response relationship between walking and the attenuation of inherited weight

OBJECTIVE

Genetic factors account for 40%-70% of the variation in body mass index (BMI). We sought to test whether moderate intensity physical activity affected parent-offspring relationships for body mass index and regional adiposity in 26,587 female and 6428 male walkers surveyed in the United States in 2000.

METHODS

Survey questionnaires provided self-reported usual walking distance, height, weight, and waist circumference, and mother's and father's adiposity (1=lean, 2=normal, 3=overweight, and 4=very overweight). Regression analyses were used to test whether the contribution of parental adiposities to the walkers' body mass indexes and waist circumferences diminished with walking.

RESULTS

In the most sedentary group (walking < 1.5 km/d), average parental adiposity was a significant determinant of the walkers' body mass indexes and waist circumferences (female: P < 10(-15); male: P < 10(-13)). Greater walking distance significantly diminished the effect of average parents' adiposity on the walkers' body mass indexes (female: P < 10(-10); male P = 0.003) and waist circumferences (female: P < 10(-6); male P = 0.01). Compared to the most sedentary female walkers, the effect of parental adiposity was reduced 36% for body mass indexes and 41% for waist circumferences (corresponding reductions in men were 36% and 46%, respectively).

CONCLUSION

These results suggest that moderate intensity physical activity attenuates inheritance of both total and regional adiposity in a dose-dependent manner.

Impact of walking on life expectancy and lifetime medical expenditure: the Ohsaki Cohort Study

OBJECTIVE

People who spend a longer time walking have lower demands for medical care. However, in view of their longer life expectancy, it is unclear whether their lifetime medical expenditure increases or decreases. The present study examined the association between time spent walking, life expectancy and lifetime medical expenditure.

METHOD

The authors followed up 27,738 participants aged 40-79 years and prospectively collected data on their medical expenditure and survival covering a 13-year-period. Participants were classified into those walking <1 and ≥1 h per day. The authors constructed life tables and estimated the life expectancy and lifetime medical expenditure from 40 years of age using estimate of multiadjusted mortality and medical expenditure using a Poisson regression model and linear regression model, respectively.

RESULTS

Participants who walked ≥1 h per day have a longer life expectancy from 40 years of age than participants who walked <1 h per day. The multiadjusted life expectancy for those who walked ≥1 h per day was 44.81 years, significantly lower by 1.38 years in men (p=0.0073) in men and 57.78 years in women, non-significantly lower by 1.16 years in women (p=0.2351). In addition to their longer life expectancy, participants who walked ≥1 h per day required a lower lifetime medical expenditure from 40 years of age than participants who walked <1 h per day. The multiadjusted lifetime medical expenditure for those who walked ≥1 h per day was £99 423.6, significantly lower by 7.6% in men (p=0.0048) and £128 161.2, non-significantly lower by 2.7% in women (p=0.2559).

DISCUSSION

Increased longevity resulting from a healthier lifestyle does not necessarily translate into an increased amount of medical expenditure throughout life. Encouraging people to walk may extend life expectancy and decrease lifetime medical expenditure, especially for men.

Moderate exercise improves leucocyte function and decreases inflammation in diabetes

The genesis and progression of diabetes occur due in part to an uncontrolled inflammation profile with insulin resistance, increased serum levels of free fatty acids (FFA), proinflammatory cytokines and leucocyte dysfunction. In this study, an investigation was made of the effect of a 3-week moderate exercise regimen on a treadmill (60% of VO₂(max) , 30 min/day, 6 days a week) on inflammatory markers and leucocyte functions in diabetic rats. The exercise decreased serum levels of tumour necrosis factor (TNF)-α (6%), cytokine-induced neutrophil chemotactic factor 2 alpha/beta (CINC-2α/β) (9%), interleukin (IL)-1β (34%), IL-6 (86%), C-reactive protein (CRP) (41%) and FFA (40%) in diabetic rats when compared with sedentary diabetic animals. Exercise also attenuated the increased responsiveness of leucocytes from diabetics when compared to controls, diminishing the reactive oxygen species (ROS) release by neutrophils (21%) and macrophages (28%). Exercise did not change neutrophil migration and the proportion of neutrophils and macrophages in necrosis (loss of plasma membrane integrity) and apoptosis (DNA fragmentation). Serum activities of creatine kinase (CK) and lactate dehydrogenase (LDH) were not modified in the conditions studied. Therefore, physical training did not alter the integrity of muscle cells. We conclude that moderate physical exercise has marked anti-inflammatory effects on diabetic rats. This may be an efficient strategy to protect diabetics against microorganism infection, insulin resistance and vascular complications.

[Physical activity and training against obesity]

A short review deals with the role of physical activity in the prevention and treatment of obesity, in order to avoid cardio-metabolic consequences of accumulation of the fat. Community-level interventions are necessary, based on estimations of the physical activity. Mechanisms and effects of the proper training on the body fat and muscle are summarized, and practical advices are presented for implementation of the regular physical activity.

Lower prevalence of hypertension, hypercholesterolemia, and diabetes in marathoners

PURPOSE

To test whether the prevalence of hypertension, hypercholesterolemia, and diabetes declines with marathon participation independent of annual running mileage.

METHODS

Cross-sectional associations of self-reported medication use in 62,284 male and 45,040 female participants of the National Runners' Health Study adjusted for age, diet, alcohol, and annual distance run.

RESULTS

By self-report, 31.7% of men and 29.1% of women ran 0.2 and 0.8 marathons per year, 8.6% of men and 4.4% of women ran between 1.0 and 1.8 marathons per year, and 3.8% of men and 1.5% of women ran an average of >or=2 marathons per year. The men's odds ratio per marathons per year run was 0.85 for antihypertensive (P < 0.0001), 0.87 for LDL-cholesterol-lowering (P = 0.002), and 0.52 for antidiabetic medication use (P < 0.0001). Compared with nonmarathoners, men who averaged 0.2-0.8 marathons per year had 13% lower odds for antihypertensive medication use, 22% lower odds for LDL-cholesterol-lowering medication use, and 67% lower odds for antidiabetic medication use. Marathon participation was also associated with lower LDL-cholesterol-lowering and antidiabetic medication use in women, but not when adjusted for annual distance run. Each additional hour required to complete their marathon had odds ratio of 1.31 and 1.22 for men's antihypertensive and LDL-cholesterol-lowering medication use and 2.01 for women's antidiabetic medication use (all P < 0.0001). Among all runners (marathoners and nonmarathoners combined), prevalence in the use of all three medications decreased in association with the length of the longest usual run, independent of total annual mileage.

CONCLUSION

Prevalence of hypertension, hypercholesterolemia, and diabetes decreases with the frequency of marathon participation independent of annual running distance. This may be due to the inclusion of longer training runs in preparation for marathons or to genetic or other innate differences between marathon and nonmarathon runners.

Relationship of running intensity to hypertension, hypercholesterolemia, and diabetes

PURPOSE

To estimate the independent relationships of running intensity with antihypertensive, LDL-cholesterol-lowering, and antidiabetic medication use when adjusted for running volume (km x d(-1)).

METHODS

Self-reported medication use was compared cross-sectionally to running pace (m x s(-1) during usual run) in 25,552 male and 29,148 female National Runners' Health Study participants.

RESULTS

The men ran a mean +/- SD of 5.2 +/- 3.1 km x d(-1) at 3.3 +/- 0.5 m x s(-1) (8.3 +/- 1.4 min x mile(-1)) and the women 4.7 +/- 2.9 km x wk(-1) at 3.0 +/- 0.4 m x s(-1) (9.2 +/- 1.8 min x mile(-1)). When adjusted for kilometers per day, each meter-per-second increment in intensity in men and women reduced the odds for antihypertensive drug use by 54% and 46%, respectively, reduced the odds for LDL-cholesterol-lowering medication use by 55% and 48%, respectively, and reduced the odds for antidiabetic medication use by 50% and 75%, respectively (all P < 0.0001). Compared with men who ran slower than 10 min x mile(-1), the odds for medication use in those who ran or exceeded a 7-min x mile(-1) pace were 72% less for antihypertensive, 78% less for LDL-cholesterol lowering, and 67% less for antidiabetic medications (the corresponding odds reductions in women were 61%, 64%, and 87%, respectively, for 8 min x mile(-1) or faster versus slower than 11 min x mile(-1)). Although usual running pace correlated significantly with a 10-km performance (male, r = 0.55; females, r = 0.49), usual pace remained significantly related to lower use of all three medications in men and antihypertension and antidiabetic medications in women when adjusted for a 10-km performance.

CONCLUSIONS

Although these results do not prove causality, they show that exercise intensity is inversely associated with the prevalence of hypertension, hypercholesterolemia, and diabetes independent of exercise volume and cardiorespiratory fitness (10-km performance), suggesting that the more vigorous the exercise, the healthier the health benefits.