The CONT group will not receive any intervention during study participation and undergo usual medical treatment and surveillance during the duration of the study.

Cardiorespiratory fitness will be measured with the 2-minute step test. Participants will be marching in place for 2 minutes and are encouraged to use a chair for balance or do the assessment seated if standing is too difficult. They should be lifting their legs about 6 inches off the ground, as if they were stepping onto a curb from the road. The tester will count the number of times the participant raises their right leg off the ground.

Lower body strength will be evaluated using the 30 second chair stand test. The participant is seated in the middle of the chair, back straight, feet approximately shoulder width apart and placed on the floor. Arms are crossed at the wrists and held against the chest. At the signal "go," the participant rises to a full body stand and then returns to the initial seated position. The participant is encouraged to complete as many full stands as possible within 30 seconds.

The TUG evaluates lower body strength, balance, and agility. The patient sits in a chair and on the command "go", the patient rises from the chair, walks 3 meters at a self-selected pace, turns around an obstacle, walks back to the chair and sits down. Test results may also be quantified assessing the time (seconds) needed to complete the assessment.

The FRAIL Scale is a short, five item assessment designed to identify frailty without face-to-face administration. The questions address Fatigue, Resistance, Ambulation, Illness, and Loss of weight (FRAIL). Scores range from 0 (robust heath status) to 5 (frail) with an intermediate category for pre-frail. Research has shown that within the geriatric fracture population, higher scores on this assessment have been shown to be associated with increased length of hospitalization, surgical complications, and more likely discharge to a rehabilitation facility rather than home making it a helpful short screen to gauge risk in the surgical population.

Maximum capacity to squeeze with each hand may be assessed using a hand grip dynamometer. Each hand may be assessed three times.

The SPPB is a short battery of performance tests of lower extremity functioning. The tests measure gait speed, standing balance, and lower extremity strength and power. To test gait speed, patients are instructed to walk an 8-foot walking course at their usual pace with assistive devices if needed. Four progressively more challenging positions are used to test balance (bipedal [feet next to each other], semi-tandem [one foot slightly in front of the other], and full tandem [one foot in front of the other]). To test lower extremity strength, patients are asked to stand up and sit down five times as quickly as possible and are timed from the initial sitting position to the final standing position at the end of the fifth stand.

Physical activity may be measured objectively using wearable accelerometry. Accelerometer data will include estimated average metabolic equivalents expended daily and in hours/week as well as time in sedentary, low, moderate, and vigorous activity.

The SARC-F questionnaire is a short 5-item battery containing observational assessments that is a rapid diagnostic test for sarcopenia. There are 5 SARC-F components: Strength, Assistance with walking, Rise from a chair, Climb Stairs, and Falls.

Min = 0; Max = 10; higher score = higher risk for sarcopenia

Expired carbon monoxide will be evaluated using a CO analyzer (coVita Smokerlyzer Breath CO Test). The CO assessment is a rapid and noninvasive method quantify CO in the blood and illustrate current smoking habits.

The Edmonton Frail Scale is a reliable measure for frailty that is easy to use, captures the multidimensional aspects of fatigue, and presents the level of frailty along a continuum so that change over time can be captured. The semi-structured interview collects data across 9 frailty domains: cognition, general health status, functional independence, social support, medication use, nutrition, mood, continence, and functional performance. Scores fall within one of 5 categories (not frail, vulnerable, mild frailty, moderate frailty, severe frailty) and range from 0 (not frail) to 17 (severe frailty).

Demographics may be collected at baseline via self-reported survey. These include date of birth, education, income, zip code, and household composition.

Developed to assess injuries as well as discomfort from exercise. This survey will be administered to the EX cohort at the end of the intervention period at timepoint T1.

QoL may be assessed with the validated 30-item self-assessment questionnaire of the European Organization for Research and Treatment of Cancer (EORTC QLQ-C30, version 3.0). It includes five multi- item functional scales (physical, role, emotional, cognitive, and social function), three multi-item symptom scales (fatigue, pain, nausea/vomiting), and six single items assessing further symptoms (dyspnea, insomnia, appetite loss, constipation, diarrhea) and financial difficulties. Scores are derived according to the EORTC scoring manual.

All of the scales and single-item measures range in score from 0 to 100. A high scale score represents a higher response level.

Thus a high score for a functional scale represents a high / healthy level of functioning, a high score for the global health status / QoL represents a high QoL, but a high score for a symptom scale / item represents a high level of symptomatology / problems.

Fatigue may be assessed with the Multidimensional Fatigue Inventory (MFI) which is a 20-item, multidimensional self-assessment questionnaire. It covers five different dimensions of fatigue (general, physical, reduced activity, reduced motivation, and mental). Scores are derived by summing the answers (five-stage scale) of the appropriate items.

Min = 20; Max = 100; higher score = less fatigue

Physical activity patterns during a patient's leisure time may be assessed using the Godin Leisure Time Exercise questionnaire. The questionnaire asks patients to recall, during a seven-day period, the frequency to which they participated in strenuous, moderate, and mild exercise. The Godin questionnaire is short and easy to complete.

Min = 0; Max = none; higher score = more activity

Smoking history and habits may be assessed using the PROMIS smoking assessment questionnaires. The questionnaire asks patients about their smoking habits, quit attempts, health expectations, and coping expectations.

Cognitive function may be measured by the 8-item PROMIS questionnaire. The questionnaire assesses patient-perceived cognitive deficits including mental acuity, concentration, verbal and nonverbal memory, verbal fluency, and perceived changes in these cognitive functions.

Min = 8; Max = 40; higher score = better cognitive function

The Patient-Generated Subjective Global Assessment (PG-SGA) is a patient-reported instrument for assessment of nutrition status in patients with cancer. The PG-SGA short form is completed by patients and screens for nutritional risk and deficit.

Min = 0, Max = 36; higher score = worse nutrition status

The PRO-CTCAE is a patient-reported outcome measure developed to evaluate symptomatic toxicity in patients on cancer clinical trials. The PRO-CTCAE item library contains 124 items representing 78 symptomatic toxicities. Specific items can be selected to create an individualized form specific to a disease or treatment group.

To assess the impact of NAT and esophagectomy on healthcare utilization, participants may complete a validated healthcare utilization form.

This assessment may collect information on participants' knowledge of available supportive care resources prior to treatment and information they receive from their healthcare providers.

The BPI is a 9-item, self-assessment questionnaire that has been largely validated. The BPI measures both the intensity of pain (sensory dimension) and interference of pain in the participant's life (reactive dimension). It also asks the participant about pain relief, pain quality, and participant perception of the cause of pain.