Regular physical activity has long been considered as a main condition for a healthy lifestyle. This idea was recently strengthened with some new scientific evidence linking regular physical activity to a set of physical and mental health benefits (Biddle, 1993; Dishman, 1992; Gill, 1986; Gilroy, 1989; Gruber, 1986; Kesaniemi et al., 2001; King et al., 1989; Vilhjalmsson and Thorlindsson, 1992).
Determinants of sport and physical activity participation in adults are well researched. A lot of studies establish this influenced behavior according to demographic, biological, psychological, behavioral, social, cultural, and physical environmental factors (Bauman et al., 2002; Dishman, 1982; Sallis and Hovell, 1990; Sallis et al., 1992; Sallis and Owen, 1999; Trost et al., 2002). Furthermore, there are many well documented reports about the quantification of physical activity in several fields (work, home activities and sports) according to geographic, social and cultural backgrounds (Bauman et al, 2009; Rutten and Abu Omar, 2004; Sjostrom et al., 2006).
Paradoxically, few studies have investigated the qualitative description of training procedures used by people perceived as physically active. To our knowledge, no study aimed to accurately describe what active people do when practicing specific sports or exercises. Yet, this approach could improve practice environment as well as knowledge about the way these people respect their commitment. Specific literature provides a great amount of information about the motives involved in physical activities according to gender and age (Brunet and Sabiston, 2011; Leit et al., 2002; Mc Cabe and Ricciardelli, 2004; Miller et al., 2000) and shows a significant effect of these variables. Therefore, it seems relevant to explore in depth details of training sessions with people practicing regular sports session related to age, gender and motives.
In Europe, 27% of the population over 15 years old claims to workout without supervision at least once a week during their free time (European Commission Report, 2010). Representing a total of 14 million people in France (Lefebvre and Thiery, 2010), this population could be defined as self-trained people since they are not registered in any social structure. Investigating this specific population appears to be relevant because self-regulatory training such as goal setting or self monitoring progress contributes to keeping them physically active (Dishman, 1982). Among the sports currently practiced in France, swimming is one of the most popular one representing 3 millions of regular self-trained people among female, male, young and older adults (Muller, 2005).
Most research concerning leisure swimming have focused on health benefits such as anthropometric indicators (Cox et al. 2010), effect in blood pressure (Cox et al., 2006; Tanaka et al., 1997), decrease in morbidity risks (Kapplan et al., 1996) or general well being (Huttunen et al., 2004). Determinants in leisure swimming participation have been less investigated. Biernat (2012) corroborated previous studies highlighting the importance of the socio-demographic determinants of active forms of leisure time. Reasons for participating in a regular leisure swimming practice have also been investigated (Hastings et al., 1995) and have shown the importance of fitness, achievement and sociability. To our knowledge, no study has investigated accurately the quantification and the contents of practice in leisure swimmers. Social statistic researches (Lefebvre and Thierry, 2010; Muller, 2005) and leisure studies (Idefi, 2008) present swimming rates participation among all the physical activities. In epidemiological reports (Bauman et al, 2009; Rutten and Abu Omar, 2004; Sjostrom et al., 2006) measures of leisure swimming quantification is often included in aerobic activities such as walking, running or cycling and impair accurate knowledge about self-training procedures in leisure swimming. Furthermore, researches aiming objective measurements by actimetry or accelerometry in order to avoid bias of self-reported data are unable to investigate activity in aquatic environment (Troiano et al., 2008).
Thus, the purpose of the actual study was to describe swimming sessions from regular self-trained swimmers from a quantitative and qualitative point of view. We used accordingly Multiple Correspondences Analysis (MCA, Le Roux et al., 2008) in order to unravel the complex interactions between age, gender and the contents of session variables, and detect typology of self-trained swimmers.
387 self-trained adult swimmers (60.2% of male and 39.8% of female) accepted the participation in this study. Age and gender are described in Table 1. In order to avoid demographic and seasonal effects (Rifas-Shiman et al., 2001; Wilcox et al., 2000), swimmers were recruited in a specific urban context, during two weeks in Paris (France). In order to examine regular self-trained swimmers only, were excluded from this study swimmers practicing less than once a week, as well as swimmers supervised and coached during their sessions, or the one swimming according for medical purpose.
All self-reported parameters were age, gender, practice frequency, supervision in physical activity experiment, main training target, main reason for swimming choice, swimming session duration and distance, most used swimming stroke and material, quality of the training control, and training evolution during a year. Age, swimming session duration and distance were quantitatively measured and accordingly coded to a qualitative scale (Table 2). Others parameters were qualitatively evaluated by numerous ordinal and nominal variables. The training control quality was evaluated by the capacity to describe the last swimming session with no specific instruction ("Can you describe your last swimming session accurately?"). Parameters used to code the training control quality into the session description were: the distance, the variety of used swim strokes, the effectiveness of interval set, the control of intensity and the occurrence of recovery period (Mujika, 1998).
Participants were recruited through the French website http://www.nageurs.com. This website registers more than 1000 weekly visits and focuses on the ability to describe one's own swimming session as well as displaying news about swimming practice in Paris (France). Thus, recruited people from this website could be considered as very concerned about their swimming practice. Before any data collection, ethics consent was granted through the French National Ethics Committee. Once participants logged themselves into the website, they were invited to participate in a study aiming to describe the substance and motives concerning their leisure swimming sessions. An electronic informed consent form was filled in and a confidential username and password were created. Once logged in, participants had access to the online survey. This type of survey method was used since it has a faster response rate, it yields less missing responses, and it provides equivalent scores when compared to paper-and-pencil survey methods (Lonsdale et al., 2006).
Distance and duration variables were averaged according to gender and age in order to describe sessions training from a quantitative standpoint. Subjects who responded with unknown duration or distance were excluded from this first analysis. Distance and duration variables were reported according to qualitative scale (see Table 2) and Chi 2 test was performed to assess gender effect on distance and duration session. In the same way, modalities of material used in relation to gender were tested by identical test. The level of significance was set at .05.
A total of 12 variables were considered and the corresponding data were organized according to a Burt table matrix where each row corresponds to one participant, and each column to a variable (Greenacre, 2007). With 387 rows and 12 columns, this matrix has been investigated through the multiple correspondences analysis (MCA). MCA is a multivariate technique of investigation that converts a matrix of data into a graphical display in which matrix's rows and columns are depicted as points (Greenacre and Hastie, 1987...