The Impact of dietary changes and PA on weight loss

Overweight and obesity are more prevalent among Canadian people (PHAC, 2011). In order to prevent and cure obesity rather than only addressing its effects, coordinated measures are required given the frequency of obesity-related comorbidities (Blissmer et al., 2006). In overweight and obese populations, increasing energy expenditure effectively prevents weight gain and lowers body weight (Hill et al., 2012, Jakicic, 2009). The effectiveness of weight-control techniques that enhance energy expenditure through PA can thus be predicted (Hill et al., 2012; Jakicic, 2009).

The current study evaluated the impact of a 12-week weight loss challenge on PA, motivation, and weight loss in a for-profit fitness facility. Another goal of this study was to look at how sustainable any changes in the assessed outcomes were, given that weight loss and increased MVPA can have an effect on long-term health (WHO, 2009).

Taking part in the 12-week weight loss challenge was not linked to greater weight reduction or an increase in MVPA when compared to a "do as you do" control group, in contrast to study assumptions and prior research (Jolly et al., 2011). Our results demonstrated a substantial temporal effect on weight loss in both conditions, with a drop in BMI in the intervention group from baseline to Time 1 approaching significance (p =.056). The observed drop in BMI was not maintained three months after taking part in the weight loss challenge, in line with research on weight loss maintenance (Stubbs et al., 2011). However, in contrast to our prediction, no appreciable change in MVPA was observed in any condition during the experiment. According to our theories and empirical study (Edmunds et al., 2007; Silva et al., 2010;

In both the short- and long-term, regardless of condition, Teixeira et al. (2012)a) found a favorable correlation between greater weight loss and increased MVPA with the more autonomous regulations for exercise.

Study Participants Compared to Those in Earlier Research

It is helpful to employ descriptive statistics on pertinent study variables to provide results the context they need to be understood in light of previous research and inferential statistics. Females in their middle years who are primarily Caucasian made up the sample for the current study. According to Wu, Gao, Chen, and van Dam (2008), the majority of participants in weight loss programs are typically between the ages of 36 and 55, with a reported mean age of 42.4 years (Shaw et al., 2006). Age and ethnicity have not been clearly linked in the literature to the success of the intervention for weight loss (Greaves et al., 2011). When studies report their results by gender, men report more weight reduction than women do (Morgan, Warren, Lubans, Collins, and Callister, 2011). This is because women often participate in weight loss therapies to a higher extent than men do (e.g., Boutcher & Dunn, 2009). Participants in the current study were categorized as overweight based on baseline measurements (PHAC, 2011). This is common in studies looking at the effectiveness of weight loss programs for samples that are either overweight or obese (Gardner & Hausenblas, 2004; Rowley, Daniel, Skinner, Skinner, White, & O'Dea, 2000; Slentz et al., 2005). (Appel et al., 2011; Lien et al., 2009; Silva et al., 2010). When obese people are the focal cohort, BMI reductions are greater than when overweight people are involved (i.e., weight loss of at least 5% of baseline body weight) (Stubbs et al., 2011). It should be emphasized that BMI-based programs for weight loss rarely include participants who are considered to be of normal weight. Given the circumstances,

During the recruitment process and in accordance with our ethical application, people who were deemed to be of "normal" weight based on BMI were not rejected. As a result, 20% (n = 8) of the current sample had BMI readings that were considered to be "normal."

Regarding PA levels, participants in the current study may be different from those normally enlisted in weight loss treatments. Eighty eight percent (88%) of those who participated in the intervention condition (n = 37) said they were physically active enough to reap health benefits, and eighty one percent (n = 34) said they were sufficiently active for both fitness and health benefits (Godin, 2011). This is in stark contrast to the majority of weight reduction studies using MVPA in middle-aged populations, with most interventions looking at people who were classed as sedentary or had low levels of MVPA behavior at baseline (Rowley et al., 2000; Slentz et al., 2005; Stubbs & Lavin, 2013). (Gardner & Hausenblas, 2004; Lien et al., 2009; Silva et al., 2010).

The majority of the participants claimed their exercise behavior was associated with greater autonomous reasons when we looked at the present sample's exercise motives at baseline. Similar results are reported by PA programs that support SDT (Deci & Ryan, 2002) and assess behavioural management of activity (Duncan et al., 2010; Silva et al., 2010; Teixeira et al., 2012a). The fact that the participants belonged to a for-profit fitness facility and that the majority were sufficiently active to reap the benefits of improved health and fitness did not come as a surprise (Duncan et al., 2010; Silva et al., 2010).

The Impact of dietary changes and PA on weight loss

Given the impact of excess weight on the occurrence of numerous "lifestyle diseases" and the resulting strain on health care resources, weight loss in the overweight and obese is of particular concern (Stubbs et al., 2012). Choosing the most efficient

Although it appears a mix of dietary adjustments and higher PA is necessary, the behavioral techniques needed for weight loss remain elusive (Wu et al., 2008). (Stubbs & Lavin, 2013). The current study provided an evidence-based approach to target weight loss by adopting techniques to raise MVPA and enhance healthy food choices.

Our results demonstrate that a slight decline in BMI was observed in both study circumstances. Although many programs (Greaves et al., 2011; Powell et al., 2007) report a weight reduction in the intervention condition and a weight increase or maintenance in the control condition, reporting a decrease in both is not entirely novel (Diabetes Prevention Program Research Group, 2002; Tuomilehto et al., 2001; Waters, St. George, Chey, & Bauman, 2012). The intervention condition lost weight largely during the weight loss challenge, whereas the control group lost weight primarily during the follow-up, according to an analysis of BMI scores by condition in the current experiment.

The slight weight reduction and subsequent partial return in the intervention condition are consistent with intervention research (Cook & Schoeller, 2011; Stubbs & Lavin, 2013). The control group's reported weight loss, however, might have been an artifact of that group's experience, a reaction to the measurement technique, treatment diffusion, or the participant's awareness of taking part in an experimental study (Waters et al., 2012). Although participants in the control condition did not sign up for the weight loss challenge, 89.10% of them said at baseline that they would want to weigh less, suggesting that they may have been involved in weight loss efforts as well. Over the duration of the 12-week weight loss challenge, the intervention condition's weight loss was modest and less than the average reported weight reduction in the literature (Shaw et al., 2006). (Shaw et al., 2006). Most weight loss methods that

lasted three months or longer, included increased PA, improved eating practices, and showed an average BMI reduction of 0.4 kg/m2 (Shaw et al., 2006), with more weight loss seen in interventions lasting six months or longer (Sharma, 2007). It should be mentioned that a weight loss of 5–10% is often regarded by healthcare professionals as successful and is connected with considerable changes in health risk status (Stubbs et al., 2011). Although the average reduction in BMI within the intervention condition was 0.64 kg/m2, exceeding the average reported weight loss (Sharma, 2007), it was insufficient to change health risk status because it represented only about 2% of the total amount of body weight lost (1.9 kg or 4.18 lbs per person).

There could be a number of reasons why the BMI decreased less than anticipated. Donnelly et al. (2009) found that weight decreases of 5-7.5 kg were associated with an intensity and duration of MVPA, but the current sample was already extremely active and no evidence of enhanced MVPA was seen. Greater weight loss success may lie more in the difference between previously and newly adopted MVPA behaviors than in the absolute amount of MVPA, as the majority of weight loss interventions examine the effectiveness of MVPA in previously sedentary individuals (Rowley et al., 2000; Slentz et al., 2005; Stubbs & Lavin, 2013). In contrast to weight loss, sustained enough MVPA may promote the benefits of weight maintenance or the avoidance of weight gain (Cook & Schoeller, 2011; Stubbs & Lavin, 2013).

The weight loss intervention study has taken note of the idea of exercise non-responders (Boutcher & Dunn, 2009; Cook & Schoeller, 2011; King et al.; 2009). The most likely causes include an increase in sedentary behavior, a concurrent decrease in incidental, non-exercise PA, and/or an increase in calorie intake.

because of the elevated MVPA intake (Boutcher & Dunn, 2009; Colley, Hills, King & Byrne, 2010; Cook & Schoeller, 2011; Thomas et al., 2012). According to Colley et al. (2010), PA interventions should include methods to keep accidental PA from changing in order to prevent this from happening. The more intense the PA prescription, the more the increased dietary intake, according to a thorough examination of the reasons why people do not lose more weight after PA interventions (Thomas et al., 2012). The research has also found additional elements that may prevent weight reduction, such as a person's personal history of weight loss and gain, the quantity and quality of their sleep, and hormonal, genetic, and metabolic variations (Boutcher & Dunn, 2009; Cook & Schoeller, 2011). At baseline, 97.60% of the intervention condition claimed having tried to lose weight in the past, with 73.80% reporting having tried during the previous year, despite the fact that the present study did not specifically ask about history of weight loss and weight regain. 28.60% of people who said they had a history of weight loss or gain also said they had participated in weight loss challenges at the same commercial fitness facility.

PA Interventions' Impact on PA

In contrast to the study's hypothesis and previous studies on MVPA intervention (Belanger-Gravel et al., 2010; Greaves et al., 2011), the present study's intervention condition did not experience a significant rise in MVPA at any point in time. There are numerous plausible causes for this. First off, the 12-week weight loss challenge's lack of increased MVPA may be a result of participants' initial self-reported MVPA levels. Regardless of condition, participants in the current study reported being physically active enough to reap the benefits for both their health and fitness on average (Godin, 2011). This implies the possibility of a "ceiling effect," when the

Participants may have been maintaining an existing appropriate level of MVPA without increasing it (Brownson et al., 2000; Kerr et al., 2010). As a result, the MVPA carried out in this study may have maintained the participants' weights rather than causing them to lose weight, which is an interesting finding given that new research suggests that adequate MVPA may have a stronger impact on weight-loss maintenance than weight loss itself (Stubbs & Lavin, 2013). Studies with participants who were active before the intervention also indicated smaller effect sizes than those with previously sedentary participants, according to a review of therapies meant to promote MVPA in adults (Conn et al., 2011).

A distortion of MVPA behavior could also account for the lack of increased MVPA. Due to their membership in a for-profit gym, they may have been biased by social pressure to report higher MVPA levels (Shephard, 2003; Waters et al., 2012). 'Gym-goers' may overestimate their self-reported PA if they report the time spent at the gym rather than the time spent exercising, according to studies (Shephard, 2003). Additionally, it seems that out of the three intensities questioned, moderate intensity PA is the one that is overstated the most (Valanou, Bamia & Trichopoulou, 2006).

The observed decrease in MVPA in the control condition from baseline to Time 1 and the subsequent reported increase in MVPA from Time 1 to Time 2 may both be explained by resentful demoralization, in which the participants in the control condition may have felt cheated of the intervention treatment and become discouraged (Onghena, 2005). The effect of the intervention treatment inflates as a result of resentful demoralization, giving the impression that it is more effective than it actually is (Onghena, 2005). The two of them working together may have lessened the resentful demoralization effect.

groups weren't split up randomly, therefore the control condition could always choose the treatment (by registering and paying for the Challenge).

Last but not least, self-report assessments may not have accurately recorded the level of adherence to the prescribed amount and/or intensity of exercise. Exercise adherence rates are challenging to quantify with accuracy, and treatments aimed at previously inactive people have been shown to have low- to moderate adherence rates (Linke, Gallo & Norman, 2011). Despite the fact that our sample was thought to be active at baseline, it is likely that more people adhered to the amount and type of exercise advised during the intervention, though probably not entirely. It has been demonstrated that the intensity of the prescribed exercise has an impact on adherence, with higher intensities of exercise leading to less adherence and an overall lower amount of activity (Perri et al., 2002). It's also interesting to note that people who are overweight or obese react to imposed exercise intensity differently than people who are normal weight, reporting greater resentment and lower adherence when intensity is even 10% higher than what they would self-select (Ekkekakis & Lind, 2006). Higher intensity and longer duration were the two elements of the exercise prescription explicitly targeted to cause a weight reduction response because the sample in the current experiment was already active. According to Stubbs and Lavin (2013), the combined effect of being previously active people who performed enough MVPA may have lessened the impact of the weight loss intervention on BMI.