## 2 Current Prehabilitation Programs
### Incidental Exercise and Inactivity  
Detecting specific prescribed physical activity is an essential component of any remote monitoring prehabilitation system. However, the detection and analysis of incidental activity and inactivity provides a more precise view of activity levels during the prehabilitation period.  
Incidental activity is any physical activity performed outside the prescribed prehabilitation program. The most common way of measuring incidental activity in oncology is through detecting step count ([PERSON] et al., 2018). Our model was designed for tracking different types of physical activity. Tracking steps in our model translates as a walking activity at different intensities.  
A key factor that has a negative influence on prehabilitation outcomes is inactivity. Most inactivity studies have used the bed rest model. Short-term bed rest (five days) in older adults is characterized by a significant loss in lean mass and strength, posing significant health consequences ([PERSON] et al., 2018). [PERSON] et al. (2018) found that 14 days of bed rest in elderly adults significantly reduced muscular mechanical work and efficiency during walking and reduced VO2 max by 12%. The study also found that elderly people needed at least three 65-min physical rehabilitation sessions per week over a period of two weeks to return to the same fitness level prior to bed rest ([PERSON] et al., 2018). Other studies have also found in older healthy adults that 10 days of bed rest has detrimental effects on muscular strength,  
\begin{table}
\begin{tabular}{c c c c} \hline
**Prehabilitation Period** & **Frequency of Exercise** & **Activities/Modalities** & **Intensity** \\ \hline \multicolumn{4}{c}{Supervised Prehabilitation} \\ \hline no record ([PERSON] et al., 2018) & 45–60 min, 2 times per week & treadmill, rowing, and resistance exercises (leg press, chest press and lateral pull down) & moderate \\ six weeks ([PERSON] et al., 2018) & 20–30 min, 5 times per week & cross trainer, rowing, cycling & moderate and vigorous \\ four weeks average ([PERSON] et al., 2018) & 30 min, 3 to 4 times per week & walking, cycling, jogging and resistance & moderate \\ two-four weeks ([PERSON] et al., 2018) & 60 min, 60 min, & exercise & \\ two-four weeks ([PERSON] et al., 2018) & 62 times per week & aerobic training, resistance exercises with & moderate and vigorous \\ \hline \multicolumn{4}{c}{Unsupervised Prehabilitation} \\ \hline four weeks ([PERSON] et al., 2018) & 50 min, 3 times per week & walking, running, cycling and resistance exercises & light, moderate and vigorous \\ two weeks ([PERSON] et al., 2018) & 30 min daily & pulmonary exercises– extensive breathing & no record \\ \hline \end{tabular}
\end{table}
Table 1: Examples of exercise parameters used in supervised and unsupervised prehabilitation programs for cancer patients undergoing abdominal surgery.  
walking distance and speed, functional parameters, and aerobic fitness [13]. Table 2 shows a summary of changes in physical fitness of the elderly after a period of bed rest [13; 14; 26]. The remote monitoring prehabilitation system discussed in this paper can identify periods of inactivity by analyzing accelerometry data that is transmitted to the cloud. Real-time transfer of data to the cloud is advantageous to the healthcare staff and enables them to respond swiftly to a system alert. Our model also has the ability to detect accumulation of inactivity over longer periods, and this data is stored in the patient database to use for the credit calculation, as explained in Section.