## 3 Dataset and Data Pre-Processing  
### Dataset  
For our study, we relied on data gathered through an online questionnaire regarding recreational runners who felt musculoskeletal discomfort. The online questionnaire included 14 questions. Each question was included in the dataset with a corresponding feature name.  
1. The age of the recreational runner (Age).
2. The height of a recreational runner (Height).
3. The weight of the recreational runner (Weight).
4. The gender of the recreational runner (Gender).
5. The experience of the recreational runner (Experience).
6. Whether the recreational runner feels any musculoskeletal discomfort (e.g., pain, tightness, heaviness) related to running activity (Musculoskeletal Discomfort)
7. If there is any discomfort, specify the area of the body in which it occurs (Symptom Area). The possible choices are: 1. Lower back 2. Knee 3. Calf muscle 4. Hip 5. Sole 6. Thigh 7. The intensity of the pain felt by the discomfort (Pain Intensity). The possible values are on a scale of one to ten: 1. 0-3--No pain or slight pain. 2. 4-6--Moderate pain. 3. 7-8--Intense pain. 4. 9-10--Insufferable pain.
9. The occasion on which the discomfort occurs (Irritability--WHEN). The possible choices are: 1. When the recreational runner starts running. 2. When the recreational runner stops running. 3. During running.
10. The duration of the discomfort (Irritability--DURATION). The possible choices are: 1. The discomfort does not stop until the next training session. 2. The discomfort lasts for one or two hours after the running session but stops until the next session. 3. The discomfort lasts while running but stops later on. 11. The intensity of the discomfort (Irritability--INTENSITY). The possible choices are: 1. Increases by three degrees (according to the Pain Intensity Scale). 2. Increases one or two degrees. 3. Remains constant. 12. The effect the discomfort has on running (Severity--RUNNING). The possible choices are: 1. No significant effect. 2. Affects the running distance or the rhythm of running. 3. Halts the running session. 13. The effect the discomfort has on everyday life (Severity--LIFE). It is a yes-or-no question. 14. The effect the discomfort has on everyday functional activities (Severity--MOBILITY). It is a yes-or-no question.  
Based on the answers given by the recreational runners, a dataset was built through which we sought to classify the category that a recreational runner belongs to. There are six categories, each with its own set of advice/guidelines. These advice/guidelines are:  
1. Reduce the training load by 30%; complete musculoskeletal functional release exercises, stretching, strengthening exercises, and functional exercises.
2. Reduce the training load by 50%; complete musculoskeletal functional release exercises, stretching, strengthening exercises, and functional exercises.
3. Cessation of training for one week followed by musculoskeletal functional release exercises, stretching, and strengthening exercises.
4. Cessation of training for two weeks followed by musculoskeletal functional release exercises and stretching exercises.
5. Cessation of training for three weeks followed by musculoskeletal functional release exercises and stretching exercises.
6. Seek medical advice and cease training for at least three weeks, followed by musculoskeletal functional release exercises and stretching exercises.  
The last seven questions on the questionnaire can be amalgamated into three main factors named:  
1. PAIN--Involves question (8), and its values are based on the scale value of the Pain Intensity.
2. IRRITABILITY--Involves questions (9), (10), and (11), and its values are low, moderate, and high.
3. SEVERITY--Involves questions (12), (13), and (14), and its values are low, moderate, and high.