Exciting news – this week the Sedentary Behaviour Research Network published an updated definition of the terms “sedentary” and “sedentary behaviour” in French and English in the journals Applied Physiology, Nutrition and Metabolism and Movement & Sport Sciences – Science & Motricité.
In brief, the new definition states that to be engaging in “sedentary behaviour”, you must meet three very basic criteria:
- You must be expending very little energy (≤1.5 Metabolic equivalents)
- You must be sitting or lying down
- You must be awake
Older definitions tended to focus exclusively on energy expenditure, which made it unclear whether certain activities (e.g. standing still, sleeping) were sedentary or not. This new definition clarifies these issues.
But more broadly, why was there a need for a new definition for sedentary behaviour?
Well, because currently people use the term sedentary to describe a variety of things. For example, some researchers use the term sedentary to refer to someone who is sitting down (that’s how I use it). Other researchers refer to someone as sedentary simply because they are not getting enough exercise, even though they may spend little or no time sitting down. The term “inactivity” is similarly used to describe these two separate and mutually exclusive situations.
The problem is that if you’re looking for research on sitting and other “sedentary behaviours”, a Pubmed or Google Scholar search brings back a bunch of irrelevant papers that are actually talking about the lack of physical activity. And you might also miss relevant papers that are labeled using a term which is different than the one you are using. I’ve been involved in two separate systematic reviews looking at the health impact of sedentary behaviour in recent years, and this ambiguity in terms made things much more difficult and time consuming.
A similar example of this issue is the term “football”, which means one thing here in North America, and something completely different in the rest of the world. If you search for “football” on Pubmed, you get some papers on American football, some others on Australian football, and some on what we North Americans usually refer to as soccer. Similarly, if you did a pubmed search for “soccer”, you might miss relevant papers that use the term “football” instead. Either way, it makes it much more difficult to find relevant information, it wastes a tremendous amount of time trying to determine if papers are relevant, and it can ultimately lead to confusion over what a paper is actually talking about.
So, the members of the Sedentary Behaviour Research Network got together and created an updated definition of sedentary behaviour and inactivity, in both English and French:
We suggest that journals formally define sedentary behaviour as any waking behaviour characterized by an energy expenditure ≤1.5 METs while in a sitting or reclining posture. In contrast, we suggest that authors use the term “inactive” to describe those who are performing insufficient amounts of MVPA (i.e., not meeting specified physical activity guidelines).
Nous suggérons que les revues définissent de façon formelle le comportement sédentaire comme une situation d’éveil caractérisée par une dépense énergétique ≤1,5 METs en position assise ou allongée. En revanche, nous suggérons que les auteurs utilisent le terme « inactif » pour décrire les individus ayant un niveau insuffisant d’activité physique d’intensité modérée à intense (MVPA), c’est-à-dire, n’atteignant pas le seuil d’activité physique recommandé.
The definition has already been endorsed by the Canadian Society for Exercise Physiology and La Société Française des Professionnels en Activités Physiques Adaptées, and I would encourage other organizations in this field to do the same. Please cite the letter when defining sedentary behaviour in your papers, and please distribute it to other individuals who may find it useful. Finally, please refer people to this definition when acting as a peer reviewer.
I’d like to give a huge thanks to the 52 SBRN members who participated in the drafting of the new definition and signed their names to the below papers (including many of the most well-known researchers in this area from around the world). Thanks also to Drs Gilles Thoni and Jean-Philippe Chaput for translating the definition and accompanying letter into French.
And don’t forget that SBRN is free to join – just visit www.sedentarybehaviour.org.
The definition can be cited as:
- Sedentary Behaviour Research Network. 2012. Standardized use of the terms “sedentary” and “sedentary behaviours”. Appl Physiol Nutr Metab. 37: 540–542.
- Réseau de Recherche sur le Comportement Sédentaire. 2012. Utilisation standardisée des termes « sédentarité » et « comportements sédentaires ». Appl Physiol Nutr Metab. 37 : 543–545.
Sedentary Behaviour Research Network (2012). Letter to the Editor: Standardized use of the terms “sedentary” and “sedentary behaviours” Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme PMID: 22540258