2.1. Study design

We used a narrative-based qualitative approach with open-ended interviews to explore exercise experiences of patients. Narrative analysis is an effective way to understand less structured, yet rich and in-depth descriptions of thoughts, feelings, and meanings [33], and has been used in studies of cancer patients [34, 35] and their exercise behaviors [36]. In this study, narrative analysis facilitated exploration of the rationale underlying time-spent on exercise and on exercise activities [37, 38].

2.2. Study setting and participants

This study was conducted at an internal chest ward with 52 beds housed in a medical center with 1,500 beds in central Taiwan. This ward specializes in caring for adults with respiratory problems (lung and breathing) in which about 60% of them are diagnosed with lung cancer. Averages of two to three hospitalized patients/week with metastatic lung cancer receive diagnostic examinations, treatments, symptom management, or palliative care.

Purposeful sampling was used to identify potential participants [39]. The inclusion criteria were as follows: (1) older than age 20 years; (2) diagnosed with metastatic lung cancer; (3) spoke Chinese or Taiwanese; (4) admitted to the hospital; (5) either currently or past had irregular or regular exercise activities (i.e. having exercise habits) [40, 41] in the hospital or at home; and (6) understood the research purpose and agreed to participate in the study. The exclusion criteria were as follows: (1) diagnosed with stage I ~ IIIB lung cancer; (2) not admitted to the hospital; (3) reported no exercise before and after cancer diagnosis; (4) refused to participate in the study, (5) declined to audio-record the interview, and (6) physical infirmities (e.g., too sick to talk). All eligible patients were identified and referred to trained interviewer by two authors (PHC and GCC).

2.3. Ethics

Ethical approval was obtained from the Institutional Review Board of Taichung Veterans General Hospital, Taiwan (Certificate of approval: C10188). Patients provided written informed consent prior to participating in the study.

2.4. Procedures and data collection

Authors in this study were trained in qualitative research and interviewing at Master’s or Ph.D level. Each participant was interviewed face-to-face by a Master’s-level interviewer (YLL) who received training in qualitative research and interviewing. One author (YLL) approached eligible inpatients and explained to them the purpose and procedures of the study. After obtaining written informed consent, background information of each participant was recorded, and an interview was scheduled. Background information included the following participant characteristics (age, sex, marital status) and disease and treatment-related information, including time since diagnosis, metastasis sites, current cancer treatments, and the performance status using the Eastern Cooperative Oncology Group (ECOG) scale [42].

Methods of data collection were in compliance with the principles of narrative interviews [43, 44]. A quiet and comfortable interview room provided a peaceful and trustful ambiance for interviewing participants and caregivers. Participants agreed to share their experiences of exercising before and after their diagnosis of metastatic lung cancer. For those who agreed to participate in the study, the interview began with the following question: ‘can you talk about your thoughts and experiences on exercise?’ in accordance with an interview guide (Table 1). Each participant was interviewed individually for a duration of 30–45 minutes. All interviews were audio-recorded and transcribed within 48 hours. Transcriptions were all de-identified and stored electronically for analysis.

Download:

• PPT
  PowerPoint slide
• PNG
  larger image
• TIFF
  original image

Table 1. Interview guide.

https://doi.org/10.1371/journal.pone.0230188.t001

2.5. Qualitative data analysis

We followed Floersch and associates’ principles of narrative analysis [45] and established the credibility of the analyses [43, 46]. Two authors (PHC and YLL) had working experience in the study setting for over 10 years and ensured the accuracy of the contents and contexts transcribed from the audio-recording after the interview and invited interviewees to confirm their transcribed messages [37, 47]. To gain details of the rich messages and thick descriptions from the interviews, we used analyst triangulation [45]: i.e., three authors (PHC, CRL, and YHL) were assigned to independently read, repeatedly reflect, constantly compare cancer- and exercise-related words, sentences and situations, and collaboratively discuss narratives to identify the findings consistent with participants’ experiences and semantic expressions. For disagreements, we checked and discussed with the interviewer (YLL) about the interview scenarios to represent participants’ thoughts or exercise experiences again. The themes and participants’ quotes were constructed [48] based on a drop-down list and data validation feature in the Excel software (Microsoft, 2016 version). Finally, the last author (YHL) confirmed and approved findings of the main themes, quotations, and interpretations.

Initially, 32 eligible participants with metastatic lung cancer were invited to participate in this study. Two participants refused to enroll; and two agreed, but their voices were too soft to be recorded. We interviewed 28 participants, four of which were excluded for having non-metastatic lung cancer (two in stage IB, one in stage IIIA, and one in stage IIIB of the disease) after rechecking the electronic medical records. Finally, data saturation was reached with the 24th patient with metastatic lung cancer with exercise experiences. This sample size of 24 was considered appropriate for constructing specific information about a specific phenomenon in a qualitative study [49]. The main themes were captured from the dialogues of all individual narratives and related contexts [43].

4.1. Thematic findings

To summarize exercise behaviors, we identified three primary themes: (1) modifying exercise such as shortening time, lowering speed, narrowing field, or increasing frequency to maximise physical functions; (2) living with frustrations and symptoms such as breathlessness, fatigue, pain, or metastasis-induced immobility, but still exercising; and (3) doing exercise to sustain hopes, inner power, and life, also encouraged by self-confidence, social supports, and religious belief.

4.2. Secondary findings

From interview transcriptions, we classified various components of exercise as shown in Fig 1. Secondary findings included: (1) adopting walking as their main form of exercise because of its convenience; and (2) among patients with severe symptoms, adjusting exercise towards shorter time durations and shorter distances, slower speeds, and higher frequencies.

Download:

• PPT
  PowerPoint slide
• PNG
  larger image
• TIFF
  original image

Fig 1. The components of exercise extracted from participants with metastatic lung cancer.

Irregular is defined that participants adopted various duration, timing, times, and frequencies in combination with exercise types, locations, or accompanying partners.

https://doi.org/10.1371/journal.pone.0230188.g001

Walking was the most common form of exercise, both before and after the cancer diagnosis. Nine participants exercised at levels of moderate-to-heavy exertion and resistance before cancer diagnosis, but after cancer diagnosis, they stopped exercising altogether. Following cancer diagnosis, most participants adapted exercises according to their physical conditions, such as mild-to-moderate exertion with individualized durations, frequencies, modes, timings, and locations, such as home-based rehabilitation programs. Seven participants who had had no previous exercise habits started walking after diagnosis. When feeling well, most participants wanted to do exercise without a partner, but some liked exercising with a spouse or family members. A subset of participants often adopted ‘irregular’ durations, timings, times, and frequencies in combination with exercise types, locations, or accompanying partners with the hope to maintain a healthier lifestyle. Finally, four participants stopped exercising after diagnosis because of their declining physical or bedridden conditions.

5.1. Methodological considerations

Results from this narrative analysis expand on existing literature examining patients with advanced lung cancer [30, 50–52]. This study focused on daily physical activities, which were modified by participants themselves according to their physical, psychological, social, and spiritual capabilities, and revealed that patients reported diverse ranges of exercise. In addition, previous studies mostly examined the effects of designed exercise programs for participants with metastatic lung cancer [9, 19–25, 51, 53]. In contrast, our narrative study put emphasis on exploring situational exercise experiences before and after a cancer diagnosis.

Through a simple interview guide and a reliable setting to gather rich information from participants’ narratives, we reached the conclusion that participants with metastatic lung cancer have strong exercise intentions to adjust their exercise behaviors along with their treatment plans [54], in spite of cancer- and treatment-related symptoms and side effects. The findings of this narrative analysis strongly suggest that a standardized exercise guideline of a total 150-minute moderate-intensity exercise on a weekly basis might not be readily achievable for patients with late-stage or metastatic lung cancer [11, 37, 55]. In fact, exercise guidelines, such as resistance, balance, and stretching exercise programs, were suggested to be customized for fitting cancer patients with metastatic disease or severely weakened physical conditions [12, 23, 56–60].

5.2. Primary findings

Exercise helped our participants with metastatic lung cancer surmount adversities due to their declining physical capacity in a brave manner [61] and continue their treatment plans [12]. In our study, participants believed that their expectations of exercise were not only achievable [52], but also boosted themselves to be healthy cancer survivors. For those who had no previous exercise behaviors, they also accepted suggestions from other people and began exercising either after diagnosis or after starting treatment [50]. As caused by physical capacity that declined relative to their past conditions, one should recognize that symptoms such as breathlessness, weakness, and fatigue, were usually taken as early warning signals of the disease [29].

In addition, our participants experienced unique sensations of breathing fresh air and increasing vital lung capacity during exercise, even though they did not show a direct effect on the lung function. Since no evidence to support irregular exercise can enhance lung capacity, health care providers should support patients’ positive feelings as well as educate them the correct concepts about exercise. Similar situation was also found in one of the participants who reported the thought that exercise could excrete toxins of chemotherapy through sweating. In the experiences from both cases suggest that some patients may have high or even incorrect expectations about the benefits of exercise. Health care professionals should support patients, but, in the meantime, bring them more correct information about taking exercise. Furthermore, exercise should be individually prescribed and tailored based on symptoms, goals, and preferences. It would be necessary to instruct participants about the strategies to adjust exercise intensity, duration, type, or environment, to fit their physical conditions, and to prevent them from over-training [14].

Most of our participants indicated that they always wished they could walk for longer distances and for longer durations, although they understood cancer could worsen their body conditions drastically. According to our findings, exercise capacity was one of the crucial signals of maintaining their hopes of survival [62, 63]. With reductions of the intensity or duration of exercise, exercise became possible when participants felt stronger to fight cancer and treatment-related symptoms. We noticed that such enhanced hopes were found, even in those diagnosed with metastatic lung cancer [62]. Those participants who exercised after being diagnosed with cancer or receiving anticancer treatments also believed their inner power might have driven them to become healthier. One of our female participants said that religious belief was important in maintaining her exercise, a finding that is consistent with other studies on healthy people [64] and other cancer patients [65]. Consistent with previous studies [9, 32], we found that social supports from family, friends, and physicians were also needed in helping patients to change their exercise behaviors, especially for older patients with advanced cancer.

5.3. Secondary findings

We found that walking was the most acceptable form of exercise for our participants, because it required low exertion, no requirement, was self-paced, low-cost, and not limited in time and space [14, 31]. Our participants sometimes treated their walking performance as an indicator of their symptoms, level of physical mobility and cancer progression. This finding is consistent with previous studies using 6-minute walking distance as an objective outcome in exercise testing and interventions [55, 66–69]. In clinical practice, for physically weaker populations, suitable amount of exercise is recommended to prevent over-training and over-exertion [14, 66, 70].

Exercise is an effective way to balance internal homeostasis and body coordination [29]. In our study, we found seven different components of exercise reflected the diversity of contents and situations in exercise, namely: type, duration, timing, times, frequency, location, and partner. An interesting phenomenon was that participants often changed duration, timing, times, and frequency according to their self-assessed effects rather automatically. The physiological responses and sensations would protect the subjects from the deleterious effects of exercise and make the subjects adjust their exercise strategies [29]. For example, the type of exercise varied from light to heavy in intensity, encompassing aerobic activity, resistance exercise, balancing, and stretching. Therefore, we classified this type as ‘irregular’ because of quantitative and qualitative factors that could compromise exercise capabilities of patients with metastatic lung cancer [9, 14].

In summary, for these active patients with metastatic lung cancer adjusted their exercise activities to strengthen their psycho-spiritual power while faced adversities of cancer and treatments. Furthermore, patients may even benefit more from their family members or caregivers receiving education on how to prepare patients to fit a balanced exercise schedule, by adjusting its type, intensity, speed, and duration [15, 28, 71].

5.4. Limitations of the study

Several limitations of our study are described below. First, our sample included patients who took exercise activities either before or after a diagnosis of metastatic lung cancer. The findings may not be generalizable to patients who have not engaged in physical activity or who are in early stage lung cancer patients. Second, it is unclear to what extent social desirability influenced the narrative data obtained from patients reporting retrospectively on their exercise experiences before cancer diagnosis. Third, limited to the cross-sectional narrative study design, we were unable to explore the trajectory of exercise experiences across cancer process due to not flowing of the situational changes of disease, symptoms, exercises adjustment and patients’ feelings across time. Thus, a longitudinal exploration of patients exercise experiences in lung cancer patients would be needed in the future. Finally, in this study, we only explored patients who either had exercise before or after cancer diagnosis, we did not explore those who never do exercise and who are in very worse conditions without physically active. Future study would be also needed to expand the scope to them and to help them develop acceptable exercise activities and enhance the positive side of cancer process.