Motivation for weight loss and association with outcomes in a lifestyle intervention: comparing emerging adults to middle aged adults.

BACKGROUND: Emerging adults (EAs) ages 18-25 are at high risk for overweight/obesity, but little is known about their motivations for weight loss or how these may differ from those of middle aged adults (MAs) and relate to treatment outcomes. PURPOSE: The purpose of this study was to examine potential differences in weight loss motivations between EAs and MAs and determine the association between motivation and engagement/outcomes in a weight loss trial. METHODS: Data were pooled from two behavioural weight loss interventions: one targeting EAs (n = 52) and one targeting MAs ages 40-60 (n = 101). Motivation, attendance, dietary self-monitoring and weight change were measured in both trials across 3 months of treatment. RESULTS: Emerging adults were less motivated by health concerns than MAs (p < .05). Motivation to lose weight in order to improve appearance was of similar importance for both MAs and EAs but demonstrated differential associations with treatment variables. Appearance-related motivation was associated with higher program engagement for MA but was associated with poorer weight loss for EAs. Overall engagement, weight loss and retention were worse for EAs than MAs (ps < .05). CONCLUSIONS: Specific motivations for weight loss were associated with treatment outcomes, but effects varied by developmental stage. Findings of this study highlight the potential differences between motivation to initiate weight loss efforts and motivation to successfully change weight-related behaviours. Future research should explore methods for intervening directly on motivation within the context of weight control interventions among EAs.

Validation of the Stanford Leisure-Time Activity Categorical Item (L-Cat) using armband activity monitor data.

OBJECTIVE: Accurate assessment of physical activity (PA) in public health and healthcare settings remains a challenge given limitations of existing brief assessment tools. The Stanford Leisure-Time Activity Categorical Item (L-Cat), a single item with six categories, has previously demonstrated excellent reliability and adequate validity relative to pedometer steps. However, pedometers cannot assess key dimensions of PA intensity or duration. METHODS: We evaluated the L-Cat's criterion validity and sensitivity to change relative to objectively measured Sensewear armband activity monitors among 76 adults with overweight/obesity (mean age 50.8 ± 11.9 years, BMI = 33.1 ± 3.4 kg m-2) at baseline and end of a 6-month behavioural weight management pilot trial. RESULTS: At baseline, L-Cat category was associated with armband-measured daily steps (Spearman's ρ = 0.41, p < 0.001), total weekly minutes of moderate/vigorous-intensity PA (MVPA) (ρ = 0.40, p < 0.001) and weekly minutes of MVPA accumulated in bouts ≥10 min (ρ = 0.47, p < 0.0001). Participants increasing ≥1 L-Cat category from baseline to 6 months had greater increases in steps (1,110.1 ± 1,852.1 vs. -18.0 ± 2,005.6 steps/d, p = 0.032), total minutes of MVPA (145.7 ± 180.6 vs. -2.1 ± 215.8 min/week, p = 0.007) and greater weight losses (-7.4 ± 7.7% vs. -3.1 ± 4.8%, p = 0.013) than those who stayed the same/decreased L-Cat categories. CONCLUSION: The L-Cat demonstrated adequate criterion validity and excellent sensitivity to change relative to objectively measured PA among behavioural weight management pilot trial participants. The L-Cat may be particularly useful for identifying individuals at lower activity levels and when using all six categories.

Examination of whether early weight loss predicts 1-year weight loss among those enrolled in an Internet-based weight loss program.

One-month weight loss (WL) predicts posttreatment WL in face-to-face interventions; however, whether this holds true within Internet programs is unknown. This study examined whether 4-week WL predicts WL following a 12-week Internet program and at 6 and 12 months follow-up. A total of 181 participants (body mass index=33.4±5.5 kg m(-)(2); 83.1% female) received a 12-week behavior-based Internet WL program consisting of weekly video lessons. Participants were given a daily WL, calorie and physical-activity goal and asked to enter these data on the study website weekly. Personalized feedback was provided. Using 4-week WL, individuals were categorized as 'early nonresponders' (<2.0% WL) or 'early responders' (⩾2.0% WL). Early nonresponders had significantly lower WL than early responders at 3 (-1.3±3.8% vs -6.3±4.3%), 6 (-1.7±5.1% vs -5.8±5.2%) and 12 months (-0.05±6.8% vs -2.7±6.3%, P<0.05). The odds of achieving a ⩾5% WL were 8.5 (95% confidence interval (CI), 3.3-22.1), 3.4 (95% CI, 1.4-8.3) and 2.6 (95% CI, 0.93-7.4) times lower in early nonresponders, compared with early responders at 3, 6 and 12 months, respectively. Compared with early responders, early nonresponders viewed fewer video lessons and self-monitored less often across the 12-week intervention (P<0.05). This study provides initial evidence that a 4-week WL of <2.0% places an individual at an increased risk of failing to achieve clinically significant WL following an Internet program.

A pilot randomized controlled trial testing the effects of a routine-based intervention on outcomes in a behavioural weight loss programme.

BACKGROUND: Structured routines aimed at eating and sleep have been successfully employed in weight loss interventions for children. Although such routines are discussed in lifestyle modification programmes for adults, they are not a primary focus. PURPOSE: The purpose of this study is to determine if establishing healthy eating and sleep routines may improve outcomes in a behavioural weight loss (BWL) intervention. METHODS: Twenty-five overweight/obese participants (age = 52.4 ± 9.8; body mass index = 33.5 ± 4.1) were randomly assigned to either a 4-week routine-based intervention (ROU) targeting regular eating and sleep or an education control before beginning an 18-week BWL intervention. RESULTS: Routine-based intervention participants reported adhering to eating routines, with increased 'on-schedule' eating (p = 0.007) and decreased 'off-schedule' eating (p = 0.002) but showed no change in 'on-schedule' sleep (p = 0.74). However, contrary to our hypothesis, ROU participants lost less weight than controls after 6 weeks of BWL (2.3 ± 2.5 vs. 4.6 ± 2.6 kg, p = 0.04) and achieved only modest weight loss over the full 18 weeks (ROU: 3.2 ± 4.6 vs. education control: 5.8 ± 5.7 kg, p = 0.23). CONCLUSIONS: Focusing initially on establishing healthy sleep and eating routines led to poorer, rather than better, subsequent weight loss outcomes. Further studies using a longer initial intervention period or focusing on only sleep or eating behaviour are needed to determine whether establishing routines for eating and sleep behaviours can enhance weight loss in adults.

Weight-loss maintenance in successful weight losers: surgical vs non-surgical methods.

OBJECTIVE: As large weight losses are rarely achieved through any method except bariatric surgery, there have been no studies comparing individuals who initially lost large amounts of weight through bariatric surgery or non-surgical means. The National Weight Control Registry (NWCR) provides a resource for making such unique comparisons. This study compared the amount of weight regain, behaviors and psychological characteristics in NWCR participants who were equally successful in losing and maintaining large amounts of weight through either bariatric surgery or non-surgical methods. DESIGN: Surgical participants (n=105) were matched with two non-surgical participants (n=210) on gender, entry weight, maximum weight loss and weight-maintenance duration, and compared prospectively over 1 year. RESULTS: Participants in the surgical and non-surgical groups reported having lost approximately 56 kg and keeping > or =13.6 kg off for 5.5+/-7.1 years. Both groups gained small but significant amounts of weight from registry entry to 1 year (P=0.034), but did not significantly differ in magnitude of weight regain (1.8+/-7.5 and 1.7+/-7.0 kg for surgical and non-surgical groups, respectively; P=0.369). Surgical participants reported less physical activity, more fast food and fat consumption, less dietary restraint, and higher depression and stress at entry and 1 year. Higher levels of disinhibition at entry and increased disinhibition over 1 year were related to weight regain in both groups. CONCLUSIONS: Despite marked behavioral differences between the groups, significant differences in weight regain were not observed. The findings suggest that weight-loss maintenance comparable with that after bariatric surgery can be accomplished through non-surgical methods with more intensive behavioral efforts. Increased susceptibility to cues that trigger overeating may increase risk of weight regain regardless of initial weight-loss method.

Serum brain-derived neurotrophic factor is associated with reduced appetite in healthy older adults.

OBJECTIVE: Loss of appetite and body mass are common in older adults and are associated with negative consequences. Research indicates that these processes likely involve increases in serum brain-derived neurotrophic factor (BDNF). Animal and human models demonstrate that BDNF may serve a regulatory function in food intake, but no study has addressed the possibility that BDNF may be involved in appetite reduction and loss of body mass in older adults. DESIGN AND PARTICIPANTS: 34 older adults without significant neurological or psychiatric history underwent fasting blood draw and measurement of body composition. Appetite and eating behavior were assessed by questionnaire and related to serum BDNF levels. RESULTS: Partial correlations showed serum BDNF levels were inversely related to appetite (r = -.38, p = .02). No significant correlations emerged between serum BDNF and age, diet, or body composition. CONCLUSIONS: The current study extends past work and shows that BDNF is associated with appetite in healthy older adults. Further work is needed to clarify mechanisms for these findings, particularly prospective studies.

Efficiency of automatic depth in processing in the elderly.

Initial encoding of information in the elderly was examined within the framework of controlled vs automatic processing. Controlled processing demands conscious effort, whereas automatic processing is cost-free in this regard. The suggestion is that adequate encoding and storage could be hindered if semantic depth is not accessed automatically. A task developed by Warren to investigate automatic processing in young Ss was used to test whether words reached semantic levels automatically in elderly Ss. Twenty-four females, 12 young and 12 old, heard word triads. Each triad was followed by visual presentation of a single word in colored ink. For both young and old Ss, color-naming latency for the visual words was significantly higher if the word itself was present in the auditory triad. This indicated that the visual words were processed to the level of meaning automatically in both young and old Ss.