Dr. Ian Janssen, Ph.D. (Queen's)
Research summary
My population-based research program examines the role that physical inactivity and obesity play in the development of poor health in both child and adult populations. Ongoing research projects within my laboratory examine the following issues:
- Surveillance of the physical inactivity and obesity levels of the population.
- To develop evidence that will inform the improvement of physical activity and sedentary behaviour guidelines and recommendations for people of all ages (pre-school children, school-aged children and youth, adults) including research on the:
- dose-response relation between physical activity and sedentary behaviour with different health outcomes
- influence of physical activity intensity on health
- influence of physical activity patterns (e.g., bouts vs. sporadic activity, active on most days vs. weekend warrior) and sedentary behaviour patterns (e.g., prolonged sitting, breaks in sedentary behaviour) on health
- influence of different types of sedentary behaviour on health
- To examine the influence of the built environment on the physical activity, sedentary behaviour, and eating behaviours of children and youth
Graduate student training opportunities
Opportunities exist for graduate students (M.Sc. and Ph.D.) and postdoctoral fellows to develop expertise in epidemiological aspects of physical activity, sedentary behaviour, and obesity. This includes studying: 1) the measurement of these behaviours, 2) the surveillance of these behaviours, 3) the determinants of these behaviours (e.g., built environment), and 4) the outcomes of these behaviours (e.g., cardiometabolic risk factors). Although internal funding is available, prospective graduate students and postdocs are encouraged to apply to the Ontario Graduate Scholarship Program, the Heart and Stroke Foundation, the Canadian Institute of Health Research (CIHR), and other agencies that provide support for research trainees. Highly qualified applicants will receive strong support.
Current funding
Canadian Institutes of Health Research (CIHR), Heart and Stroke Foundation, and the Public Health Agency of Canada
Recent publications
RECENT PUBLICATIONS
* underlined authors represent students that I have supervised
Janssen I, Rosu A. Measuring sidewalk distances using Google Earth. BMC Med Res Methodol. 2012;12:39 (doi:10.1186/1471-2288-12-39)
Colley RC, Janssen I, Tremblay MT. Daily step target to measure adherence to physical activity guidelines in children. Med Sci Sports Exerc. 2012;44(5):977-982. (doi: 10.1249/MSS.0b013e31823f23b1)
Seliske L, Pickett W, Janssen I. Urban sprawl and its relationship with active transportation, physical activity and obesity in Canadian youth. Health Rep. In press.
Carson V, Janssen I. The mediating effects of dietary habits on the relationship between television viewing and body mass index among youth. Ped Obes. In press. (doi: 10.1111/j.2047-6310.2012.00049.x)
Shields M, Tremblay MS, Connor Gorber S, Janssen I. Measures of central obesity within body mass index categories, 1981 to 2007-2009. Health Rep. 2012;23(2):1-6.
Tremblay M, LeBlanc A, Carson V, Choquette L, Connor Gorber S, Dillman C, Duggan M, Gordon MJ, Hicks A, Janssen I, Kho M, Latimer AE, LeBlanc C, Murumets K, Okely T, Reilly J, Spence J, Stearns J, Timmons B. Canadian physical activity guidelines for the early years (aged 0-4 years). Appl Physiol Nutr Metab. 2012;37:345-356. (doi: 10.1139/H2012-018)
Tremblay M, LeBlanc A, Carson V, Choquette L, Connor Gorber S, Dillman C, Duggan M, Gordon MJ, Hicks A, Janssen I, Kho M, Latimer AE, LeBlanc C, Murumets K, Okely T, Reilly J, Stearns J, Timmons B, Spence J. Canadian sedentary behaviour guidelines for the early years (aged 0-4 years). Appl Physiol Nutr Metab. 2012;37:370-380. (doi:10.1139/H2012-019)
Colley RC, Wong SL, Garriguet D, Janssen I, Connor Gorber S, Tremblay MS. Physical activity, sedentary behaviour and sleep in Canadian children: A comparison between parent-report and direct measures and their relative association with health risk. Health Rep. 2012;23(2):1-8.
Shields M, Tremblay MS, Connor Gorber S, Janssen I. Abdominal obesity and cardiovascular disease risk factors within body mass index categories. Health Rep. 2012;23(2)1-10.
Janssen I, Ross R. Vigorous intensity physical activity is related to the metabolic syndrome independent of the physical activity dose. Int J Epid. In press. (doi: 10.1093/ije/dys038)
Carson V, Janssen I. Neighborhood disorder and screen time among 10-16 year old Canadian youth: a cross-sectional study. Int J Behav Nutr Phys Act. 2012;9:66. (doi:10.1186/1479-5868-9-66).
Kukaswadia A, Craig W, Janssen I, Pickett W. Bullying as a mediator of relationships between adiposity status and weapon carrying. Int J Public Health. In press. (doi: 10.1007/s00038-011-0329-6)
LeBlanc AG, Spence J, Carson V, Connor Gorber S, Dillman C, Janssen I, Kho ME, Sterns JA, Timmons BJ, Tremblay MS. Systematic review of sedentary behaviour and health indicators in the early years (aged 0-4 years). Appl Physiol Nutr Metab. In press.
Timmons BJ, LeBlanc AG, Carson V, Connor Gorber S, Dillman C, Janssen I, Kho ME, Spence J, Sterns JA, Tremblay MS. Systematic review of physical activity and health indicators in the early years (aged 0-4 years). Appl Physiol Nutr Metab. In press.
Janssen I. Health care costs of physical inactivity in Canadian adults. Appl Physiol Nutr Metab. In press. (doi: 10.1139/h2012-061)
Gropp KM, Janssen I, Pickett W. Active transportation to school in Canadian youth: should injury be a concern? Inj Prev. In press. (doi:10.1136/injuryprev-2012-040335)
Gee ME, Janssen I, Pickett W, Bancej CM, McAlister FA, Joffres M, Johansen H, Campbell N. Prevalence, awareness, treatment and control of hypertension among Canadian adults with diabetes, 2007-2009. Can J Cardiol. 2012;28:367-375. (doi:10.1016/j.cjca.2011.08.111)
Héroux M, Janssen I, Lee D-C, Sui X, Hebert J, Blair SN. Clustering of unhealthy behaviors in the Aerobics Center Longitudinal Study. Prev Sci. 2012;13:183-195. (doi: 10.1007/s11121-011-0255-0)
Mecredy G, Janssen I, Pickett W. Neighbourhood street connectivity and injury in youth: a national study of built environments in Canada. Inj Prev. 2012;18:81-87. (doi:10.1136/injuryprev-2011-040011)
Jackson AS, Janssen I, Sui X, Church TS, Blair SN. Longitudinal changes in body composition associated with healthy ageing: men, ages 20 to 96. Br J Nutr. 2012;107:1085-1091. (doi:10.1017/S0007114511003886)
Janssen I, Shields M, Craig CL, Tremblay MS. Changes in the obesity phenotype within Canadian children and adults, 1981 to 2007-2009. Obesity. 2012;20:916-919. (doi:10.1038/oby.2011.122)
Chaput JP, Janssen I, Spence JC. Time spent sedentary and active and cardiometabolic risk factors in children. JAMA. 2012;307:2024.
Janssen I, Boyce WF, Pickett W. Screen time and physical violence in 10 to 16-year-old Canadian youth. Int J Public Health. 2012;57(2)325-331. (doi: 10.1007/s00038-010-0221-9)
Janssen I. Midlife physical activity affects successful aging in women. Clin J Sports Med. 2011;21:71-72.
Kukaswadia A, Craig W, Janssen I, Pickett W. Obesity as a determinant of two forms of bullying in Ontario youth: a short report. Obes Facts 2011;4:469-472. (doi: 10.1159/000335215)
Mark AE, Janssen I. Influence of movement intensity and physical activity on adiposity in youth. J Phys Act Health. 2011;8:164-173.
Carson V, Pickett W, Janssen I. Screen time and risk behaviors in 10- to 16-year-old Canadian youth. Prev Med. 2011;52:99–103. (doi:10.1016/j.ypmed.2010.07.005)
Janssen I, Shields M, Craig CL, Tremblay MS. Prevalence and secular changes in abdominal obesity in Canadian adolescents and adults, 1981 to 2007-2009. Obes Rev. 2011;12(6):397-405. (doi: 10.1111/j.1467-789X.2010.00815.x.)
Bouchard DR, Héroux M, Janssen I. Association between muscle mass, leg strength, and fat mass with physical function in older adults: influence of age and sex. J Aging Health. 2011;23(2):313–328. (doi:10.1177/0898264310388562)
Warsh J, Janssen I, Pickett W. Do overweight and obese youth take longer to recovery from injury? Int J Inj Contr Saf Promot. 2011;18:143–149. (doi: 10.1080/17457300.2010.540329).
Colley RC, Garriguet D, Janssen I, Craig CL, Clarke J, Tremblay MS. Physical activity of Canadian adults: accelerometer results from the 2007 to 2009 Canadian Health Measures Survey. Health Reports. 2011;22(1):7-14.
Colley RC, Garriguet D, Janssen I, Craig CL, Clarke J, Tremblay MS. Physical activity of Canadian children: accelerometer results from the 2007 to 2009 Canadian Health Measures Survey. Health Rep. 2011;22(1):15-23.
Tremblay MS, Warburton DER, Janssen I, Paterson DH, Latimer AE, Rhodes RE, Kho ME, Hicks A, LeBlanc AG, Zehr L, Murumets K, Duggan M. New Canadian physical activity guidelines. Can J Public Health. 2011;36:36-46. (doi:10.1139/H11-009)
Tremblay MS, LeBlanc AG, Janssen I, Kho ME, Hicks A, Murumets K, Colley RC, Duggan M. Canadian sedentary behaviour guidelines for children and youth. Can J Public Health. 2011;36:59-64. (doi:10.1139/H11-012)
Shields M, Connor Gorber S, Janssen I, Tremblay MS. Bias in self-reported estimates of obesity in Canadian health surveys: an update on correction equations for adults. Health Rep. 2011;22(3):35-45.
Shields M, Connor Gorber S, Janssen I, Tremblay MS. Obesity estimates for children based on parent-report versus direct measures. Health Rep. 2011;22(3):47-58.
Carson V, Janssen I. Volume, patterns, and types of sedentary behavior and cardio-metabolic health in children and adolescents. BMC Public Health. 2011;11:274. (doi:10.1186/1471-2458-11-274)
Janssen I. The epidemiology of sarcopenia. Clin Geriatr Med. 2011;27:355-363. (doi:10.1016/j.cger.2011.03.004)
McPherson M, Janssen I, Grundy A, Tranmer J, Richardson H, Aronson KJ. Physical activity, sedentary behavior and melatonin among rotating shift nurses. J Occup Environ Med. 2011;53(7):716-721. (doi: 10.1097/JOM.0b013e31822282fd)
O’Loghlen S, Pickett W, Janssen I. Active transportation environments surrounding Canadian schools. Can J Public Health. 2011;102(5):364-368.
Carson V, Iannotti RJ, Pickett W, Janssen I. Urban and rural differences in sedentary behavior among American and Canadian youth. Health Place. 2011;17:920-928. (doi:10.1016/j.healthplace.2011.04.007)
Janssen I, Bacon E, Pickett W. Obesity and its relationship with occupational injury in the Canadian workforce. J Obes. 2011;2011:531403. (doi:10.1155/2011/531403)
Lawson J, Janssen I, Bruner M, Madani K, Pickett W. Urban-rural differences in asthma prevalence: the roles of health behaviors and obesity. Ann Allergy Asthma Immunol. 2011;107:220-228. (doi:10.1016/j.anai.2011.06.014)
Mecredy G, Pickett W, Janssen I. Street connectivity is negatively associated with physical activity in Canadian youth. Int J Environ Res Public Health. 2011;8:3333-3350. (doi:10.3390/ijerph8083333)
Holman RM, Carson V, Janssen I. Does the fractionalization of daily physical activity (sporadic vs. bouts) impact cardiometabolic risk factors in children and youth? PLoS ONE. 2011;6(10):e25733. (doi:10.1371/journal.pone.0025733)
Faulkner GEJ, Grootendorst P, Nguyen VH, Andreyeva T, Arbour-Nicitopoulos K, Auld C, Cash S, Cawley J, Donnelly P, Drewnowski A, Dube L, Ferrence R, Janssen I, LaFrance J, Lakdawalla D, Mendelsen R, Powell L, Traill B, Windmeijer F. Economic instruments for obesity prevention: results of a scoping review and modified Delphi survey. Int J Behav Nutr Phys Act. 2011;8:109. (doi:10.1186/1479-5868-8-109)