CBT+ 治疗抑郁症 (CBT+)

实验性的：主动认知行为治疗

治疗前，参与者将在固定自行车上完成 30 分钟的标准化锻炼。 参与者将在锻炼时观看 8 个标准化的 30 分钟自然纪录片视频之一。

行为的：主动认知行为治疗

治疗前，参与者将在固定自行车上完成标准化的 30 分钟有氧运动。 监督锻炼课程将包括中等强度的稳态锻炼，对应于感知锻炼的“13”或“有点困难”评级。 在整个运动过程中将持续监测心率、阻力/负荷和 RPE。 为了紧密配合各组，参与者还将在锻炼时观看 30 分钟的自然视频。

有源比较器：平静CBT

参与者将在治疗前安静休息时观看 8 个标准化的 30 分钟自然纪录片视频之一。

行为的：平静CBT

参与者将在治疗前安静休息时观看 8 个标准化的 30 分钟自然视频之一。 这些是情感中立的视频，将使两组参与者拥有相同的注意力和接触时间。

Average Self-reported Working Alliance Measured by Working Alliance Inventory (WAI)

Working Alliance Inventory-Short Revised (WAI) is a 12-item survey on experiences over a therapy session and connection with a therapist. It consists of three subscales: tasks, goals, and therapist-client bond. The total range of scores is from 12-84 with higher scores indicating a better therapeutic alliance.

Self-reported Behavioral Activation Measured by Behavioral Activation for Depression Scale (BADS)

The Behavioral Activation for Depression Scale (BADS) will be used to assess changes in behavioral activity. The scale is designed to be administered weekly to measure changes over the course of Behavioral Activation for depression. It consists of 25 questions that inquire about Activation, Avoidance/Rumination, Work/School Impairment, and Social Impairment. Each item is rated on a 7-point scale from 0 (Not at all) to 6 (Completely) with total scores ranging: 0-150 where higher scores indicate greater behavioral activation.

Change in Clinician-rated Depression Symptoms Measured by GRID-Hamilton Depression Rating Scale (GRID-HAM-D) From Intake

The GRID-HAM-D is a clinician-completed questionnaire that will be used to rate depressive symptom severity. The questionnaire is designed for adults and is used to rate the intensity and frequency of depressive symptoms by probing mood, feelings of guilt, suicidal ideation, insomnia, agitation or retardation, anxiety, weight loss, and somatic symptoms. As recommended by the Depression Rating Scale Standardization Team, Clinical Interviewers will follow the Structured Interview Guide and use GRID scoring, in which dimensions of intensity and frequency of a symptom are rated independently for each item. Total scores are calculated from each question and range from 0 to 52, with higher scores indicated greater depressive symptom severity.

Change in Self-reported Depression Symptoms Measured by Patient Health Questionnaire-9 (PHQ-9) From Week 1

The Patient Health Questionnaire-9 (PHQ-9) is a 9-question self-report instrument used to assess presence and severity of depressive symptoms, with scores categorized 0-4, 5-9, 10-14, 15-19, and 20-27 as minimal, mild, moderate, moderately severe, and severe depression, respectively.

MDD Diagnosis Measured by Structured Clinical Interview for DSM-5 Disorders (SCID)

The SCID is a clinician-administered semi-structured interview guide for making diagnoses according to the diagnostic criteria published in the American Psychiatric Association's Diagnostic and Statistical Manual for Mental Disorders (DSM-5). It provides diagnoses for inclusion and exclusionary diagnoses. Results show number of participants who meet criteria for Major Depressive Disorder (i.e., 'checked') or no longer meet criteria (i.e., 'unchecked').

Average Anhedonia Measured by Dimensional Anhedonia Rating Scale (DARS)

The DARS is a self-report measure that assesses state anhedonia across multiple domains. DARS is a 17-item survey on state anhedonia divided into four domains: hobbies, food/drink, social activities, and sensory experiences. Subjects must list two activities within each of these categories that they consider their favorite and then respond to questions regarding their interest in/enjoyment of those activities on a 5-point Likert scale from "Not at all" (0) to "Very much" (4), with total scores ranging from 0 to 68, with higher scores representing reduced anhedonia.

Average Anhedonia Measured by an Anhedonia Visual Analogue Scale (Anhedonia VAS)

An anhedonia Visual Analog Scale [VAS] with 0 indicating 'No pleasure at all' and 100 indicating 'Greatest pleasure imaginable' will be used to measure anhedonia. The VAS will be used to provide a supplementary assessment of anhedonia.

Serum Brain Derived Neurotrophic Factor (BDNF)

Serum BDNF will be quantified from a standard blood draw. Blood samples collected during Visits 1, 4, and 8 will be allowed to clot for 30 minutes and then centrifuged for ten minutes at 5500 RPM and 4 ◦C. Following centrifugation, blood serum will be extracted with samples stored at -80 ◦C until BDNF analysis. Enzyme-linked immunosorbent assay (ELISA) kits will measure the concentration of total BDNF in the serum according to the manufacturer's instructions. Each blood sample will be run in duplicate and averaged.

Change in Anxiety Measured by Generalized Anxiety Disorder 7 (GAD-7) From Intake

Generalized Anxiety Disorder 7 (GAD-7) is a self-reported questionnaire for measuring generalized anxiety disorder. GAD-7 has seven items, which measure the severity of various signs of GAD according to reported response categories of: Not at all (0 points), Several days (1 point), More than half the days (2 points), and Nearly every day (3 points). A total score is calculated ranging from 0 to 21, with higher scores indicating more severe anxiety symptoms.

Average Automatic Thoughts Measured by Automatic Thoughts Questionnaire (ATQ)

The ATQ is a 30-item instrument that measures the frequency of automatic negative statements about the self. Each item is rated on the frequency of an occurrence from "not at all" to "all the time". Total scores are the sum of all 30 items (ranging 30-150), with higher totals indicating a higher level of automatic negative self-statements.

Average Session Effectiveness Measured by Session Evaluation Questionnaire (SEQ)

Session Evaluation Questionnaire (SEQ) will be used to evaluate session effectiveness. This includes responses to twenty-one items in a 7-point bipolar adjective format questionnaire to assess how the client feels about each CBT session. The questionnaire assesses session depth, smoothness, positivity, and arousal. An overall score of the subscales will be used in this study (ranging 7-28). Higher scores indicate more favorable session evaluations.

自然关联指数 (NCI)

NCI 包含 6 个与自然连通性相关的问题。 参与者使用 7 点李克特量表进行回答，范围从 1（非常不同意）到 7（非常同意），分数越高表明自然联系程度越高。

健康史问题

健康史将被自我报告。 此外，参与者将被要求列出他们当前的药物。

人口统计调查问卷

将记录或测量人口特征，包括年龄、性别、种族、教育、婚姻状况、职业状况和家庭收入，以表征样本。

不良童年经历调查（ACES）

ACES 包含 16 个问题，涉及受访者生命的前 18 年。 参与者对于是否发生儿童不良事件回答“是”或“否”。 不良事件问题按类别分组。 参与者会针对他们所接触的每个事件类别进行评分，分数范围从 0（未接触）到 7（接触所有类别）。

Average Lyssn Generated Scores

Lyssn is an AI-powered assessment platform for recording and managing session files, and all clinical interviews and therapy sessions will be recorded on the Lyssn platform. Lyssn will process the audio files from therapy sessions to generate session-level data regarding collaboration and empathy as metrics related to the primary client ratings of working alliance, as well as generating CTRS fidelity metrics which will be used in the ongoing supervision and fidelity monitoring of all sessions.

Change in Monitor-assessed Physical Activity Measured by Accelerometry

Participants will place an activPAL on the midline of the thigh on either leg and wear the monitor during all waking hours, removing it only for water-based activities (e.g., swimming). For data to be valid, the monitor must have been worn for 20 hours on at least 4 days, including a minimum of 3 weekdays and 1 weekend day. Sleep time will be parsed out from each day's sitting/lying time automatically using PALanalysis. From these data, average minutes of sitting per day will be used to assess total sedentary time, minutes of stepping time with a cadence ≥75 and <100 will be used to assess minutes of light-intensity physical activity and minutes of stepping time with a cadence ≥100 will be used to assess minutes of moderate to vigorous physical activity (MVPA).

Change in Quality of Life Measured by the 36-Item Short Form Health Survey (SF-36)

The SF-36 assesses health-related quality of life. It consists of eight scaled scores (including vitality, physical functioning, bodily pain, general health perceptions, physical role functioning, emotional role functioning, social role functioning, and mental health), which are the weighted sums of the questions in their section. Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The higher the score the less disability (i.e., a score of zero is equivalent to maximum disability and a score of 100 is equivalent to no disability).

Change in Self-reported Physical Activity Measured by the International Physical Activity Questionnaire - Short Form (IPAQ-SF)

The IPAQ is a physical activity questionnaire that inquires about average amounts of walking, moderate physical activity, vigorous physical activity, and sitting time per week.

Change in Suicidal Thoughts Measured by the Columbia-Suicide Severity Rating Scale (CSSRS)

The C-SSRS will be used to assess and monitor suicide ideation and behavior. The severity of the ideation subscale is rated on a 5-point ordinal scale: 1 = wish to be dead, 2 = nonspecific active suicidal thoughts, 3 = suicidal thoughts with methods, 4 =suicidal intent, and 5 = suicidal intent with plan. Suicide behaviors are rated on a nominal scale that includes actual, aborted, and interrupted attempts; preparatory behavior; and non-suicidal,self-injurious behavior.