Re: Exercise, Health & You: How Much Is Enough?
Posted: Thu Apr 23, 2015 4:02 pm
NY Times article
The Right Dose of Exercise for a Longer Life
By GRETCHEN REYNOLDS
APRIL 15, 2015 5:30 AM
http://well.blogs.nytimes.com/2015/04/1 ... life/?_r=0
"Those who met the guidelines precisely, completing 150 minutes per week of moderate exercise, enjoyed greater longevity benefits and 31 percent less risk of dying during the 14-year period compared with those who never exercised.
The sweet spot for exercise benefits, however, came among those who tripled the recommended level of exercise, working out moderately, mostly by walking, for 450 minutes per week, or a little more than an hour per day. Those people were 39 percent less likely to die prematurely than people who never exercised."
NOTE: Going from zero to 150 minutes gets you a 31% benefit. Going from 150-450 minutes gets you a 39% benefit. So, for 3x the effort (150-450 minutes per week) they got only a "modest" 8% more benefit. Breaking it down, for 150 minutes, your benefit is .26 per minute. At 450 minutes, your benefit is .086 per minute. For the extra 300 minutes, your benefit is .026 per minute.
The studies...
1) Leisure Time Physical Activity and Mortality: A Detailed Pooled Analysis of the Dose-Response Relationship. JAMA Intern Med. 2015 Apr 6. doi: 10.1001/jamainternmed.2015.0533.
http://archinte.jamanetwork.com/article ... id=2212267
Abstract
IMPORTANCE:
The 2008 Physical Activity Guidelines for Americans recommended a minimum of 75 vigorous-intensity or 150 moderate-intensity minutes per week (7.5 metabolic-equivalent hours per week) of aerobic activity for substantial health benefit and suggested additional benefits by doing more than double this amount. However, the upper limit of longevity benefit or possible harm with more physical activity is unclear.
OBJECTIVE:
To quantify the dose-response association between leisure time physical activity and mortality and define the upper limit of benefit or harm associated with increased levels of physical activity.
DESIGN, SETTING, AND PARTICIPANTS:
We pooled data from 6 studies in the National Cancer Institute Cohort Consortium (baseline 1992-2003). Population-based prospective cohorts in the United States and Europe with self-reported physical activity were analyzed in 2014. A total of 661 137 men and women (median age, 62 years; range, 21-98 years) and 116 686 deaths were included. We used Cox proportional hazards regression with cohort stratification to generate multivariable-adjusted hazard ratios (HRs) and 95% CIs. Median follow-up time was 14.2 years.
EXPOSURES:
Leisure time moderate- to vigorous-intensity physical activity.
MAIN OUTCOMES AND MEASURES:
The upper limit of mortality benefit from high levels of leisure time physical activity.
RESULTS:
Compared with individuals reporting no leisure time physical activity, we observed a 20% lower mortality risk among those performing less than the recommended minimum of 7.5 metabolic-equivalent hours per week (HR, 0.80 [95% CI, 0.78-0.82]), a 31% lower risk at 1 to 2 times the recommended minimum (HR, 0.69 [95% CI, 0.67-0.70]), and a 37% lower risk at 2 to 3 times the minimum (HR, 0.63 [95% CI, 0.62-0.65]). An upper threshold for mortality benefit occurred at 3 to 5 times the physical activity recommendation (HR, 0.61 [95% CI, 0.59-0.62]); however, compared with the recommended minimum, the additional benefit was modest (31% vs 39%). There was no evidence of harm at 10 or more times the recommended minimum (HR, 0.69 [95% CI, 0.59-0.78]). A similar dose-response relationship was observed for mortality due to cardiovascular disease and to cancer.
CONCLUSIONS AND RELEVANCE:
Meeting the 2008 Physical Activity Guidelines for Americans minimum by either moderate- or vigorous-intensity activities was associated with nearly the maximum longevity benefit. We observed a benefit threshold at approximately 3 to 5 times the recommended leisure time physical activity minimum and no excess risk at 10 or more times the minimum. In regard to mortality, health care professionals should encourage inactive adults to perform leisure time physical activity and do not need to discourage adults who already participate in high-activity levels.
PMID: 25844730
2) Effect of Moderate to Vigorous Physical Activity on All-Cause Mortality in Middle-aged and Older Australians. JAMA Intern Med. 2015 Apr 6. doi: 10.1001/jamainternmed.2015.0541. [Epub ahead of print]
Abstract
IMPORTANCE:
Few studies have examined how different proportions of moderate and vigorous physical activity affect health outcomes.
OBJECTIVE:
To examine whether the proportion of total moderate to vigorous activity (MVPA) that is achieved through vigorous activity is associated with all-cause mortality independently of the total amount of MVPA.
DESIGN, SETTING, AND PARTICIPANTS:
We performed a prospective cohort study with activity data linked to all-cause mortality data from February 1, 2006, through June 15, 2014, in 204 542 adults aged 45 through 75 years from the 45 and Up population-based cohort study from New South Wales, Australia (mean [SD] follow-up, 6.52 [1.23] years). Associations between different contributions of vigorous activity to total MVPA and mortality were examined using Cox proportional hazards models, adjusted for total MVPA and sociodemographic and health covariates.
EXPOSURES:
Different proportions of total MVPA as vigorous activity. Physical activity was measured with the Active Australia Survey.
MAIN OUTCOMES AND MEASURES:
All-cause mortality during the follow-up period.
RESULTS:
During 1 444 927 person-years of follow-up, 7435 deaths were registered. Compared with those who reported no MVPA (crude death rate, 8.34%), the adjusted hazard ratios for all-cause mortality were 0.66 (95% CI, 0.61-0.71; crude death rate, 4.81%), 0.53 (95% CI, 0.48-0.57; crude death rate, 3.17%), and 0.46 (95% CI, 0.43-0.49; crude death rate, 2.64%) for reporting 10 through 149, 150 through 299, and 300 min/wk or more of activity, respectively. Among those who reported any MVPA, the proportion of vigorous activity revealed an inverse dose-response relationship with all-cause mortality: compared with those reporting no vigorous activity (crude death rate, 3.84%) the fully adjusted hazard ratio was 0.91 (95% CI, 0.84-0.98; crude death rate, 2.35%) in those who reported some vigorous activity (but <30% of total activity) and 0.87 (95% CI, 0.81-0.93; crude death rate, 2.08%) among those who reported 30% or more of activity as vigorous. These associations were consistent in men and women, across categories of body mass index and volume of MVPA, and in those with and without existing cardiovascular disease or diabetes mellitus.
CONCLUSIONS AND RELEVANCE:
Among people reporting any activity, there was an inverse dose-response relationship between proportion of vigorous activity and mortality. Our findings suggest that vigorous activities should be endorsed in clinical and public health activity guidelines to maximize the population benefits of physical activity.
PMID: 25844882
To put these in perspective, you can see the formal definitions of moderate and moderate to vigorous activity here..
http://www.cdc.gov/nccdphp/dnpa/physica ... le_2_1.pdf
While these articles may sound like they are supporting "intense" exercise, the levels in the study were no where near the level of activity that the extreme/intense exercisers are doing. These articles are 100% in line with the general recommendations linked to in the first post of this thread, 150-300 per week of moderate activity or 75-150 minutes per week of vigorous activity or a combination of both.
In Health
Jeff
The Right Dose of Exercise for a Longer Life
By GRETCHEN REYNOLDS
APRIL 15, 2015 5:30 AM
http://well.blogs.nytimes.com/2015/04/1 ... life/?_r=0
"Those who met the guidelines precisely, completing 150 minutes per week of moderate exercise, enjoyed greater longevity benefits and 31 percent less risk of dying during the 14-year period compared with those who never exercised.
The sweet spot for exercise benefits, however, came among those who tripled the recommended level of exercise, working out moderately, mostly by walking, for 450 minutes per week, or a little more than an hour per day. Those people were 39 percent less likely to die prematurely than people who never exercised."
NOTE: Going from zero to 150 minutes gets you a 31% benefit. Going from 150-450 minutes gets you a 39% benefit. So, for 3x the effort (150-450 minutes per week) they got only a "modest" 8% more benefit. Breaking it down, for 150 minutes, your benefit is .26 per minute. At 450 minutes, your benefit is .086 per minute. For the extra 300 minutes, your benefit is .026 per minute.
The studies...
1) Leisure Time Physical Activity and Mortality: A Detailed Pooled Analysis of the Dose-Response Relationship. JAMA Intern Med. 2015 Apr 6. doi: 10.1001/jamainternmed.2015.0533.
http://archinte.jamanetwork.com/article ... id=2212267
Abstract
IMPORTANCE:
The 2008 Physical Activity Guidelines for Americans recommended a minimum of 75 vigorous-intensity or 150 moderate-intensity minutes per week (7.5 metabolic-equivalent hours per week) of aerobic activity for substantial health benefit and suggested additional benefits by doing more than double this amount. However, the upper limit of longevity benefit or possible harm with more physical activity is unclear.
OBJECTIVE:
To quantify the dose-response association between leisure time physical activity and mortality and define the upper limit of benefit or harm associated with increased levels of physical activity.
DESIGN, SETTING, AND PARTICIPANTS:
We pooled data from 6 studies in the National Cancer Institute Cohort Consortium (baseline 1992-2003). Population-based prospective cohorts in the United States and Europe with self-reported physical activity were analyzed in 2014. A total of 661 137 men and women (median age, 62 years; range, 21-98 years) and 116 686 deaths were included. We used Cox proportional hazards regression with cohort stratification to generate multivariable-adjusted hazard ratios (HRs) and 95% CIs. Median follow-up time was 14.2 years.
EXPOSURES:
Leisure time moderate- to vigorous-intensity physical activity.
MAIN OUTCOMES AND MEASURES:
The upper limit of mortality benefit from high levels of leisure time physical activity.
RESULTS:
Compared with individuals reporting no leisure time physical activity, we observed a 20% lower mortality risk among those performing less than the recommended minimum of 7.5 metabolic-equivalent hours per week (HR, 0.80 [95% CI, 0.78-0.82]), a 31% lower risk at 1 to 2 times the recommended minimum (HR, 0.69 [95% CI, 0.67-0.70]), and a 37% lower risk at 2 to 3 times the minimum (HR, 0.63 [95% CI, 0.62-0.65]). An upper threshold for mortality benefit occurred at 3 to 5 times the physical activity recommendation (HR, 0.61 [95% CI, 0.59-0.62]); however, compared with the recommended minimum, the additional benefit was modest (31% vs 39%). There was no evidence of harm at 10 or more times the recommended minimum (HR, 0.69 [95% CI, 0.59-0.78]). A similar dose-response relationship was observed for mortality due to cardiovascular disease and to cancer.
CONCLUSIONS AND RELEVANCE:
Meeting the 2008 Physical Activity Guidelines for Americans minimum by either moderate- or vigorous-intensity activities was associated with nearly the maximum longevity benefit. We observed a benefit threshold at approximately 3 to 5 times the recommended leisure time physical activity minimum and no excess risk at 10 or more times the minimum. In regard to mortality, health care professionals should encourage inactive adults to perform leisure time physical activity and do not need to discourage adults who already participate in high-activity levels.
PMID: 25844730
2) Effect of Moderate to Vigorous Physical Activity on All-Cause Mortality in Middle-aged and Older Australians. JAMA Intern Med. 2015 Apr 6. doi: 10.1001/jamainternmed.2015.0541. [Epub ahead of print]
Abstract
IMPORTANCE:
Few studies have examined how different proportions of moderate and vigorous physical activity affect health outcomes.
OBJECTIVE:
To examine whether the proportion of total moderate to vigorous activity (MVPA) that is achieved through vigorous activity is associated with all-cause mortality independently of the total amount of MVPA.
DESIGN, SETTING, AND PARTICIPANTS:
We performed a prospective cohort study with activity data linked to all-cause mortality data from February 1, 2006, through June 15, 2014, in 204 542 adults aged 45 through 75 years from the 45 and Up population-based cohort study from New South Wales, Australia (mean [SD] follow-up, 6.52 [1.23] years). Associations between different contributions of vigorous activity to total MVPA and mortality were examined using Cox proportional hazards models, adjusted for total MVPA and sociodemographic and health covariates.
EXPOSURES:
Different proportions of total MVPA as vigorous activity. Physical activity was measured with the Active Australia Survey.
MAIN OUTCOMES AND MEASURES:
All-cause mortality during the follow-up period.
RESULTS:
During 1 444 927 person-years of follow-up, 7435 deaths were registered. Compared with those who reported no MVPA (crude death rate, 8.34%), the adjusted hazard ratios for all-cause mortality were 0.66 (95% CI, 0.61-0.71; crude death rate, 4.81%), 0.53 (95% CI, 0.48-0.57; crude death rate, 3.17%), and 0.46 (95% CI, 0.43-0.49; crude death rate, 2.64%) for reporting 10 through 149, 150 through 299, and 300 min/wk or more of activity, respectively. Among those who reported any MVPA, the proportion of vigorous activity revealed an inverse dose-response relationship with all-cause mortality: compared with those reporting no vigorous activity (crude death rate, 3.84%) the fully adjusted hazard ratio was 0.91 (95% CI, 0.84-0.98; crude death rate, 2.35%) in those who reported some vigorous activity (but <30% of total activity) and 0.87 (95% CI, 0.81-0.93; crude death rate, 2.08%) among those who reported 30% or more of activity as vigorous. These associations were consistent in men and women, across categories of body mass index and volume of MVPA, and in those with and without existing cardiovascular disease or diabetes mellitus.
CONCLUSIONS AND RELEVANCE:
Among people reporting any activity, there was an inverse dose-response relationship between proportion of vigorous activity and mortality. Our findings suggest that vigorous activities should be endorsed in clinical and public health activity guidelines to maximize the population benefits of physical activity.
PMID: 25844882
To put these in perspective, you can see the formal definitions of moderate and moderate to vigorous activity here..
http://www.cdc.gov/nccdphp/dnpa/physica ... le_2_1.pdf
While these articles may sound like they are supporting "intense" exercise, the levels in the study were no where near the level of activity that the extreme/intense exercisers are doing. These articles are 100% in line with the general recommendations linked to in the first post of this thread, 150-300 per week of moderate activity or 75-150 minutes per week of vigorous activity or a combination of both.
In Health
Jeff