# Practical Approach to Designing and Implementing a Recommendation System for Healthy Challenges
## 2 Materials and Methods
### User Profile
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Source of** & **Item** & **Set of Possible Values** \\
**Information** & & \\ \hline \multirow{6}{*}{User-entered} & Age group & 5–17 years. 18–64 years. 65 years or more. \\  & Gender & Male. Female. \\  & & By means of the weight and height of the users, the BMI is calculated to classify them in the corresponding group. BMI \(<\) 18.5 = underweight. 18.5–24.9 = normal weight. \\  & BMI & 25–29.9 = preobesity. 30–34.9 = class I obesity. 35–39.9 = class II obesity. \textgreater{}40 = class III obesity. \\  & & Skin diseases. Pregnancy, childbirth, or puerperium. Sleep or wakefulness disorders. \\  & \multirow{2}{*}{Special groups} & Endocrine diseases (e.g., diabetes). Diseases of the circulatory system (e.g., hypertension). Diseases of the musculoskeletal system or connective tissue (e.g., arthritis, chondropathities). None. \\  & Injuries & Upper body. Lower body. Trunk. None. \\  & Daily time available & \textless{}15\textarcdegree\). Between 15\textarcdegree\) and 30\textarcdegree\). \textless{}30\arcdegree\). \\  & Available spots & Pool. Sea. Country or city. Indoor house. Gym. \\  & Required material & Bicycle. Barbells. Sliding discs. Jumping rope. No material. Others. \\ \hline \multirow{6}{*}{SF-36} & PF & Rating for the physical function dimension (0–10) \\  & BP & Rating for the bodily pain dimension (0–10) \\  & GH & Rating for the general health dimension (0–10) \\  & V & Rating for the vitality dimension (0–10) \\  & SF & Rating for the social function dimension (0–10) \\  & MH & Rating for the mental health dimension (0–10) \\ \hline \multirow{6}{*}{sHEI-15} & FC & Rating for the fruit consumption dimension (0–10) \\  & LVC & Rating for the legume and vegetable consumption dimension (0–10) \\  & GVC & Rating for the green vegetable consumption dimension (0–10) \\  & ASC & Rating for the dimension of consumption of added sugars (0–10) \\  & WGC & Rating for the whole grains consumption dimension (0–10) \\  & DC & Rating for the dairy consumption dimension (0–10) \\ \hline \multirow{6}{*}{OSC} & SSS & Rating for the subjective sleep satisfaction dimension (0–10) \\  & IS & Rating for the insomnia dimension (0–10) \\  & HS & Rating for the hypersomnia dimension (0–10) \\ \hline \multirow{2}{*}{Acceptable Effort} & \multirow{2}{*}{AE} & \multirow{2}{*}{Obtained through the arithmetic mean of the PF and MH components.} \\ \cline{3-4}  & & BMI: Body mass index; PF: Physical function; BP: Bodily pain; GH: General health; V: Vitality; SF: Social function; MH: Mental health; FC: Fruit consumption; LVC: Legume and vegetable consumption; ASC: Added sugar consumption; WGC: Whole grains consumption; DC: Dairy consumption; GVC: Green vegetable consumption; SSSS: Subjective sleep satisfaction; IS: Insomnia; HS: Hypersomnia: AE: Acceptable effort. \\ \hline \multirow{2}{*}{Acceptable Effort} & \multirow{2}{*}{AE} & \multirow{2}{*}{Obtained through the arithmetic mean of the PF and MH components.} \\ \cline{3-4}  & & BMI: Body mass index; PF: Physical function; BP: Bodily pain; GH: General health; V: Vitality; SF: Social function; MH: Mental health; FC: Fruit consumption; LVC: Legume and vegetable consumption; ASC: Added sugar consumption; WGC: Whole grains consumption; DC: Dairy consumption; GVC: Green vegetable consumption; SSSS: Subjective sleep satisfaction; IS: Insomnia; HS: Hypersomnia: AE: Acceptable effort. \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Description of the items used for the complete characterization of the user profile. Consequently, each user is characterized by a total of 24 features, as illustrated in Table 1. Nine of these features are provided directly by the user, resulting in eight values (weight and height together form the BMI item). Additionally, there are six dimensions from the SF-36 questionnaire, six dimensions from the sHEI-15 questionnaire, three dimensions from the OSC questionnaire and lastly the Acceptable Effort (AE).