A Chronic High-Intensity Interval Training and Diet-Induced Obesity Model to Maximize Exercise Effort and Induce Physiologic Changes in Rats.

Compared to continuous-moderate or low-intensity training, high-intensity interval training (HIIT) is a more time-efficient alternative method that results in similar physiologic benefits. This paper presents a HIIT protocol that can be used to assess various health markers in a Sprague-Dawley rat model of diet-induced obesity. Female Sprague Dawley rats aged 21 days old were randomly assigned to the following groups: control (CON, n = 10), exercise-trained (TRN, n = 10), high-fat diet (HFD, n = 10), and high-fat diet/exercise training (HFD/TRN, n = 10). The control diets consisted of commercial laboratory chow with 10% kilocalories (kcal) from fat (3.82 kcal/g), and the high-fat diets (HFD) consisted of 45% kcal from fat (4.7 kcal/g). The animals had ad libitum access to their assigned diet throughout the study. After an 8 week diet induction period, the exercise cohorts completed four HIIT sessions per week for 8 weeks. Each HIIT session consisted of 10 intervals of 1 min sprints/2 min rest using a rodent treadmill with a motor-driven belt. After the 8 weeks of training, the animals were sacrificed for tissue collection. The results revealed no differences in the distance run between the TRN and HFD/TRN groups, and the training speed steadily increased over the duration of the study, with a final running speed of 115 cm/s and 111 cm/s for the TRN and HFD/TRN groups, respectively. The weekly caloric intake was decreased (p < 0.05) in the TRN group relative to the CON group but increased (p < 0.05) in the HFD/TRN group relative to the HFD group. Lastly, the animals on the HFD had greater (p < 0.05) adiposity, and the trained animals had reduced (p < 0.05) adiposity relative to controls. This protocol demonstrates an efficient method to evaluate the effects of HIIT on various physiologic outcomes in a diet-induced obesity model.

Which variations of a brief cognitive bias modification session for interpretations lead to the strongest effects?

BACKGROUND: Brief computerized programs that train less threatening interpretations (termed Cognitive Bias Modification for Interpretations, or CBM-I) can shift interpretation biases and subsequent anxiety symptoms. However, results have been inconsistent, particularly for studies conducted over the Internet. METHODS: The current exploratory study tests 13 variations of a single brief session of CBM-I, a non-CBM-I cognitive flexibility condition, a neutral condition, and a no task control condition in an analogue sample with moderate to severe anxiety. RESULTS: Results suggest that all conditions, except the neutral scenarios condition and the alternative way to improve cognitive flexibility, led to changes in interpretations (when compared to the no task control condition). Only conditions geared toward increasing imagery during CBM-I and targeting flexibility related to emotional material differed from the no task control condition on other post-training measures. CONCLUSIONS: Presenting valenced interpretations of ambiguous information during brief CBM-I, regardless of the format, can lead to changes in interpretation bias. However, most conditions did not differ from the no task control condition on other post-training assessments (and differences that did occur may be due to chance). Future trials should consider further testing of CBM-I that targets flexibility related to emotional material, and should include an increased number of sessions and trials.