Newly graduated physical therapists have received up-to-date education and training in evaluating techniques and interventions, providing a new perspective, and understanding of the field. Physiotherapists with more time in practice have acquired extensive clinical experience in the assessment of individuals with changes in body stability. It is believed that the assessment of stability in the plank exercise will depend on professional education, training, and clinical experience.

To evaluate the agreement of physiotherapists with different times of clinical practice in the assessment of body stability while performing the traditional front plank (TFP).

Cross-sectional experimental study. Healthy adults of both genders were included, with self-reported practice of moderate physical activity of at least 150 minutes a week and/or vigorous activity of at least 75 minutes a week, without reports of pain or history of injury or trauma, with previous experience in exercise of TFP, and not having performed physical exercise in the last 48 hours. After reading and accepting the Free and Informed Consent Term, the evaluation form was completed. To perform the TFP, the participants should remain for as long as possible with elbows and feet flat on the ground in line with the shoulders, hips and spine in a neutral position and posterior pelvic inclination. Based on this, a control form was prepared to record the classification of body stability by evaluators with different times of clinical practice. The form consisted of three items in which the evaluator selected only one to classify the TFP through video analysis. The items were: TFP performed with high stability, complying with all items described in the exercise for the entire period of time; TFP performed with moderate stability, complying with the items described in the exercise for more than 50% of the time; TFP performed with low stability, complying with the described exercise items for less than 50% of the time. The TFP exercise was filmed with a Sony Handycam DCR-SR65 camcorder at a distance of 2.5 meters from the subject. The same footage was sent to the recently graduated Physiotherapist and the other with seven years of clinical practice on day 1 and day 7. The Kappa Index was used for all analyzes of the degree of intra and inter-rater agreement, being interpreted: 0.81 to 1.0 – excellent; 0.6 to 0.8 – substantial; 0.4 to 0.6 – moderate; 0.2 to 0.4 – low; 0 to 0.2 – very low.

10 individuals were evaluated (five men and five women), with a mean age of 27.1 (±7.6) years, and mean body mass index of 23.4 kg/m² (±4.2). The analysis showed a low degree of agreement (Kappa=0.167) in the perception of a recently graduated Physiotherapist and an excellent one in the perception of the Physiotherapist with seven years of clinical practice (Kappa= 1.000), in different periods, in relation to body stability in the TFP.

Physiotherapists with different times of clinical practice differ in the agreement of the response in relation to body stability during the execution of the traditional frontal plank.

As this is a pilot study, the limitations are related to the sample size.