Perceived barriers for physical activity in overweight and obese adolescents and their association with health motivation

Both epidemiological studies and everyday observations of adolescent behaviours confirm the finding that adolescents with overweight and obesity are characterised by lower physical activity than their peers with normal weight. Moreover, overweight adolescents take part in PE classes and extracurricular sports less often [1, 2]. Unfortunately, despite evidence proving the benefits of physical activity for health and development (including obesity and atherosclerosis prevention), most of the children and adolescents are not physically active on a recommended level or they prefer a sedentary lifestyle [3, 4]; alternatively, both reasons occur simultaneously resulting in an accumulation of factors which have a negative impact on health and development [5].

It is, therefore, important to investigate the reasons why overweight adolescents are less active than their peers with normal weight.

The barriers perceived by young people probably have a potential influence on physical activity. Some barriers may have a stronger negative impact on engaging in physical activity than others; they may also be more specific for adolescents with excess body mass. These are primarily the so-called internal barriers resulting from low self-esteem and self-limitations, such as lack of skills and lack of energy. Overweight might have a negative impact on achieving the milestones in child development and shaping the basic motor skills in young people. It was demonstrated that obesity significantly hinders some motor activities, such as jumping, climbing or squatting. Research has also shown an inverse relationship between cardiorespiratory fitness and obesity level [6]. In some types of aerobic activities, such as running, overweight children and adolescents are unable to cover the same distance as their peers with a normal weight, as they become tired more quickly. Because of the functional and structural limitations related to obesity among children and adolescents, it is also obvious that the health-related quality of life in this group is lower in comparison with their slim peers [7].

Motivation plays a significant role in maintaining physical activity. Understanding its role in pursuing an active lifestyle is the key to tackling the problem of an insufficient amount of physical activity. This problem largely affects overweight and obese children and adolescents [8]. Most of the studies which evaluate the physical activity of obese people fail to consider the psychological factors related to obesity. However, the self-determination theory (STD) by E. Deci and R. Ryan is increasingly often quoted as the theoretical basis for the studies conducted. It is used to identify the relation among undertaking and maintaining physical activity and psychological variables in obese people [9, 10]. The SDT explains the mutual influence of internal and external factors, as well as the natural human needs which have impact on human behaviour [11, 12].

According to Edmunds et al., more is needed to maintain an active lifestyle than just internal motivation; one also needs external factors, such as peer support or trends [13]. External motivation seems, however, to be key in undertaking physical activity [14, 15].

The most important factors motivating overweight and obese adolescents to physical activity include mixed and external motives occurring under the influence of the social environment, such as the need to lose weight or to improve physical fitness. At the same time, for adolescents with normal weight, internal motives, such as pleasure and fun, are essential [16, 17, 18].

The aim of the study was to analyse the barriers to engaging in physical activity that are reported by adolescents with excessive body mass, and determine whether they perceive those barriers similarly to their peers with normal weight? Moreover, the aim was to establish whether relationships exist among the perceived barriers and the health-oriented motivation to physical activity.

The study was conducted in 2013 as part of the project funded by the Ministry of Sports and Tourism in Poland in 2013, on a representative sample of 3,346 students aged 10-16 (including 1,587 boys)

Analysis were conducted within the statutory activity of the Institute of Mother and Child, project No 510-20-65

The characteristics of participants are shown in table II. Overweight and obesity occurred in one of every eight people; twice as often in boys as in girls (p<0.001). In the younger age group, adolescents with excessive body mass comprised 18.1% and 9.7% boys and girls, respectively (p<0.001). In the older age group, there were twice as many boys with excessive body mass as their female peers (p<0.001).

The motives for engaging in health-oriented physical activity

In the general sample of adolescents with overweight and obesity, the most important reason for engaging in health-oriented physical activity, was the need to improve one’s health, while the least important one was the need to look good (tab. IV).

In gender analysis, it was noted that in girls with excessive body mass the need to look good was the strongest motive to physical activity. The most important motive among adolescents with normal weight was to be good at sport, while to control my weight proved to be the least important one. In comparison with peers with normal weight, adolescents with overweight and obesity were characterised by lower motivation to get in good shape (p=0.003) and to be fit (p=0.009). However, they had stronger motivation to control my weight, though a statistically important correlation was found only in boys (p=0.003).

No statistically significant differences were found regarding health-oriented motivation among young people with normal weight and their peers with overweight and obesity. Attention should be drawn to the tendency occurring in girls with excessive body weight: there was a greater percentage of persons with weak motivation for health in comparison with their peers with normal weight (39.5% vs. 30.5%) and analogically a lower percentage of those with strong motivation (36.1% vs. 41.2%) (fig. 1). Such a correlation was not found in boys.

Fig. 1

Table V

Multidimensional logistic regression modeling results with estimated risk (OR) of adolescents’ cumulated PA barriers perception.

Tabela V Wyniki wielowymiarowego modelu regresji logistycznej z oszacowanym ryzykiem (na podstawie ilorazu szans) postrzegania przez młodzież skumulowanych barier w aktywności fizycznej.

Variables Zmienne	B	p	OR	95% (OR)
				Coefficient interval Przedział ufności
Gender Płeć Boys (ref) Chłopcy (ref)				Upper limit Dolna granica	Lower limit Górna granica
Girls Dziewczęta	0.845	0.000	2.33	1.92	2.82
Age Wiek 13,8 lat (ref)
15,8 lat	0.516	0.000	1.68	1.39	2.02
BMI categories Kategorie BMI Normal body mass (ref) Prawidłowa masa ciała (ref)
Overweight Nadwaga i otyłość and obesity	0.542	0.000	1.72	1.29	2.30
Health-oriented motivation Motywacja dla zdrowia Strong (ref) Silna (ref)
Average Przeciętna	0.192	0.090	1.21	0.97	1.51
Weak Słaba	1.085	0.000	2.96	2.36	3.72
Constant (β) Stała (β)	1.139	0.000	0.32

Table VI

Multidimensional logistic regression modeling results with estimated risk (OR) of adolescents' cumulative PA barriers perception within the health motivation groups.

Tabela VI. Wyniki wielowymiarowego modelu regresji logistycznej z oszacowanym ryzykiem (na podstawie ilorazu szans OR) postrzegania przez młodzież skumulowanych barier w aktywności fizycznej w różnym zależności od poziomu motywacji ukierunkowanej na zdrowie.

Health-oriented motivation Motywacja dla zdrowia	Weak motivation Motywacja słaba			Average motivation Motywacja przeciętna			Strong motivation Motywacja silna
	B	P	OR (95% Cl)	B	P	OR (95% Cl)	B	P	OR (95% Cl)
Gender Płeć Boys (ref) Chłopcy (ref)
Girls Dziewczeta	0.915	0.000	2.50 (1.76-3.55)	0.976	0.000	2.65 (1.89-3.73)	0.678	0.000	1.97 (1.45-2.68)
Age Wiek 13,8 lat (ref)
15,8 lat	0.275	0.121	1.32 (0.93-1.86)	0.752	0.000	2.12 (1.52-2.97)	0.521	0.001	1.68 (1.25-2.26)
BMI categories Kategorie BMI Normal body mass Prawidłowa masa (ref)
Overweight and obesity Nadwaga i otyłość	0.920	0.001	2.51 (1.43-4.42)	0.397	0.143	1.49 (0.87-2.53)	0.370	0.116	1.45 (0.91-2.30)
Constant (β) Stała (β)	-.005	0.976	0.995	-1.116	0.000	0.327	-1.018	0.000	0.361

Numerous psychological factors which can be potential predictors of insufficient physical activity in adolescents were examined in the last two decades on the basis of the social learning theory [17, 22]. These also include the perceived facilities and barriers to undertaking physical activity. Moreover, it is an important direction in the research on adolescents with overweight and obesity.

The first objective of this paper was to identify barriers to physical activity in adolescents aged 13-16 with different BMI status. It was found that three out of five of the investigated barriers were indeed more often listed by overweight and obese adolescents than by their peers with normal weight. These barriers were among the so-called internal barriers. They resulted from the self-limitations of adolescents, relating primarily to lack of skills, energy and willpower. This is important information, because such barriers are the proof of low internal motivation for engaging in physical activity among young people with overweight and obesity [23]. Body weight was a more important factor differentiating the perception of the barriers in boys than in girls. This was probably caused by a greater percentage of girls perceiving barriers to physical activity among the study participants. In another study relating to this group of young people that did not take into account body weight, it was concluded that girls were twice as likely to perceive the barriers to physical activity in comparison with boys [24].

Another objective of the study was to investigate the extent to which the perception of the barriers to physical activity changes in a group of adolescents depending on body weight and differences in the level of health-oriented motivation to engage in physical activity.

In comparison to adolescents with a healthy body weight, young people with overweight and obesity were not motivated to physical activity by the need to get in good shape and to be good at sport; stronger motivation was the need to control weight, though a statistically significant correlation occurred only in boys.

It can be presumed that among girls dietary efforts play a greater role in controlling body weight than physical activity [25]. Polish research on eating behaviours and body weight control methods in older adolescents (aged 16-18) has found that girls follow diets three times more often than boys (or engage in other behaviour aimed at weight loss). An exception is the intensification of physical exercise noted in a greater number of boys. A proper diet (including expert-supervised diets) is followed by 60% of boys and even 90% of girls [26].

The results of the multilevel logistic regression model applied in our study showed a significant influence of health-oriented motivation on the perception of barriers to physical activity by overweight and obese adolescents. In the model oriented on different levels of motivation for physical activity, it was concluded that the excess body weight as a predictor of the perception of accumulated barriers to physical activity remained in the model only in cases of weak health-oriented motivation. In adolescents with strong and average motivation for physical activity, the excess body mass ceased to be significant for the perception of accumulated barriers to physical activity. According to Korean authors, the BMI alone explained only 17% of the variability of physical activity in adolescents with overweight and obesity, however, after adding a component compliant with the self-determination theory motivation for physical activity, the percentage rose to 49% [27].

It can be concluded that young people with excessive body weight and strong health-oriented motivation perceived barriers to physical activity similarly to their peers with normal weight. Thus, motivation was a key element, shaping overweight and obese young people’s physical activity by changing their perception of the barriers to physical activity.

Both in comprehensive preventive measures and in the treatment of obesity in adolescents, physical education (PE) teachers have a special role to play alongside parents. We might still be far away from a situation where students have an opportunity to participate in a mandatory PE lesson tailored to their individual needs, abilities and expectations. However, teachers’ help might prove to be important as a breakthrough in increasing their motivation, especially if it is health-oriented, to undertake and maintain an appropriate level of physical activity [28, 29].

Recognising the barriers to physical activity in overweight and obese adolescents might facilitate adopting an individual approach in PE classes, as well as devising effective intervention programmes aimed at ones with excessive body weight.

In overcoming the barriers to physical activity in overweight and obese adolescents, one should aim to comprehensively reduce body weight and support health-oriented motivation for physical activity.

The greatest chances of success are envisaged for the forms of assistance which include working with overweight young people and are oriented both towards the individual and the environment, supporting health-oriented motivation for physical activity.