Effects of TENS During the Performance of a Therapeutic Exercise Protocol in Individuals With Knee Osteoarthritis.

Knee Injury and Osteoarthritis Outcome Score (KOOS). It aims to evaluate the domains of pain, symptoms, activities of daily living, function related to recreation and sports, and quality of life related to the knee. Totaling 42 items, each item must be answered using a Likert scale that ranges from 0 (best score) to 4 (worst score), and the score for each subscale ranges from 0 (worst score) to 100 (best score).

The Numerical rating pain scale, a simple, easily administered scale evaluates the perceived intensity of pain, using an 11-point scale from 0, representing 'no pain', to 10, which is the 'worst possible pain'.

Pain self-efficacy questionnaire, structured into 10 items where each item is evaluated by selecting a number on a 7-point numerical scale (scores from 0 to 6), where 0 means "not at all confident" and 6 means "completely confident". The items cover different functions, from work, social activities, domestic tasks and coping with pain without medication. A total score is calculated from the sum of the scores for each of the 10 items, producing a total score that ranges from 0 to 60. Higher scores reflect stronger self-efficacy beliefs.

30 second sit and stand test. From a sitting position with feet flat on the floor and shoulder-width apart, arms crossed across the chest, the individual assessed must stand, with hips and knees fully extended. Then, he must sit down, with his lower part completely touching the seat, repeating these movements continuously for 30 seconds. The chair must be placed against the wall. The total number of complete cycles will be counted (standing up and sitting down represents one cycle).

Patient Specific Functional Scale. An easy-to-apply self-report instrument, validated for measuring disability related to specific tasks identified by the individual. The scale is made up of 11 (eleven) numbers, graduated from 0 (zero) to 10 (ten), where 0 (zero) represents inability to perform the activity and ten (ten) the ability to perform the activity at the level prior to the current condition.

manual dynamometer portable (Lafayette Manual Muscle System, Modelo 01165, Lafayette Instrument Company, Lafayette, IN). Four 5-second readings will be taken during maximal voluntary isometric contraction (MVIC) with a 30-second rest period between contractions. The first CIVM will familiarize the volunteer with carrying out the task. A new set of readings will be taken if a volunteer can perform three contractions with at least 10% variability. Strong and constant verbal stimuli will be used throughout the test. Always with the research participants' hands positioned crossed on the chest. Thus, bilateral assessments of the muscles, quadriceps, and gluteus medius will be carried out. The order of CIVM readings will be randomized to avoid collection bias. The research participant will remain in lateral decubitus with a pillow positioned between the legs, with the limb to be tested superiorly in a neutral position.

The perception of the global effect of the treatment by the research participant will be evaluated by the Global Perception of Change scale. The Global Perception of Change scale is a direct scale on the patient's self-perception when the intervention is performed. This scale consists of 11 points, ranging from -5 (worsening compared to the start of treatment), 0 (neutral) and +5 (improvement compared to the start of treatment), using the Portuguese version.

The World Health Organization Disability Assessment Schedule 2.0 short version (12 items) is a generic self-report assessment instrument developed by the World Health Organization (WHO) to assess functionality and disability during the last 30 days.For each item, a Likert-type scale will be used to define the severity of the limitation, with a score of 0 (Zero) denoting "no limitation" and 4 (four) denoting "extreme limitation or inability to function." The total score is the sum of all 12 items, where a score of 48 points represents the worst possible restriction.