Related Experiment Video
Updated: Feb 15, 2026

Collecting Hair Samples for Hair Cortisol Analysis in African Americans
Published on: June 10, 2018
Television Viewing Time, Physical Activity, and Mortality Among African Americans
Tasnim F Imran1,2, Mark Ommerborn3, Cheryl Clark3
1Brigham & Women's Hospital, VA Boston Healthcare System, Harvard Medical School, 1620 Tremont St, Boston, MA 02120.
Background:
Prolonged television viewing time, a marker of sedentary activity, is independently associated with increased all-cause mortality; however, this association has rarely been studied in African Americans. The objective of our study was to examine the association between television viewing time and mortality among African Americans by using data from the Jackson Heart Study (JHS).
Methods:
We studied 5,289 participants from the JHS study who reported television viewing time (h/day) in the JHS baseline questionnaire from 2000 through 2004. Using multivariable Cox regression models adjusted for age, sex, smoking, alcohol use, physical activity, nutrition, prevalent coronary heart disease, chronic kidney disease, diabetes, and hypertension, we computed hazard ratios to examine the association between television viewing time (≤2 h/day, 2-4 h/day, and ≥4 h/day) and mortality.
Results:
Participants had a mean age of 55 years, and 64% were women. After a median follow-up of 9.9 years (interquartile range, 9.0-10.7), 615 deaths occurred (data analysis conducted in 2017). Hazard ratios for mortality were 1.08 (0.86-1.37) for television time of 2 to 4 hours per day and 1.48 (95% CI: 1.19-1.83) for television time of greater than or equal to 4 hours per day when compared with those who watched television less than 2 hours per day (P trend = .002). When we restricted analyses to those who performed leisure-time activities, the hazard ratios for mortality were 1.10 (95% CI, 0.84-1.45) for television viewing of 2 to 4 hours per day and 1.45 (95% CI, 1.13-1.86) for more than 4 hours per day compared with the less than 2 hours per day.
Conclusion:
Our findings suggest that greater television viewing time, even among those who perform leisure-time physical activities, is associated with increased all-cause mortality among African Americans. Thus, it may serve as an indicator of a sedentary lifestyle with potential for intervention.
Related Concept Videos
Econometric Views (EViews)
Physical and Chemical Properties of Matter
Cranial Bones: Lateral View
The temporal bone forms the lower lateral side of the skull. The temporal bone is subdivided into several regions. The flattened upper portion is the squamous portion of the temporal bone. Below this area and projecting anteriorly is the zygomatic process of the temporal bone, which forms the posterior portion of the zygomatic arch. Posteriorly is the mastoid portion of the temporal bone. Projecting...
Physical Pendulum
When dealing with complicated systems, the mass moment of inertia is an important parameter, as it...
Revisionist Views of Adolescent and Adult Cognition
The Scope of Physics

