RESUMEN
UNLABELLED: Ratings of perceived exertion (RPE) were developed to provide a subjective estimation of exercise intensity during exercise but are also used to produce exercise intensities and to report the intensity of completed exercise sessions. PURPOSE: To determine the relationship between RPE assessed before, during, and after trials of RPE-based self-regulated aerobic exercise. METHODS: Twenty-six participants (10 males and 16 females) were tested for aerobic fitness. Participants completed three 30-min trials of treadmill exercise at a self-selected intensity corresponding to verbal prescriptions of light, moderate, and vigorous. Participants were instructed to adjust treadmill speed every 5 min to maintain the prescribed intensity. RPE using the OMNI picture system was taken immediately before, every 5 min during, immediately after, and 15 min after exercise. RESULTS: Treadmill speed increased during the moderate trial, and HR increased during all trials (P < 0.05). Predicted RPE and session RPE were higher than the average RPE for all sessions (P < 0.05) but not different than RPE values obtained at the end of the 30-min trials (P > 0.05). CONCLUSIONS: Findings suggest that predicted and session RPE are well matched to the exertion associated with the finishing minute of exercise sessions but are poorly matched to the majority of the exercise session. In-task RPE values tend to drift throughout exercise despite little or no change in treadmill speed and instructions to self-regulate exercise intensity. These findings indicate that RPE may be linked to exercise duration during self-regulated exercise. Additionally, session RPE ratings taken after exercise tend to reflect the close of exercise rather than the exertion associated with the exercise session as a whole.
Asunto(s)
Prueba de Esfuerzo/métodos , Esfuerzo Físico/fisiología , Adulto , Femenino , Humanos , Masculino , Consumo de Oxígeno/fisiología , Resistencia Física/fisiologíaRESUMEN
In this study, we assessed how ungraded jogging and graded walking at the same rating of perceived exertion (RPE) affect heart rate and oxygen consumption ([Vdot]O(2)). Twenty untrained participants completed a treadmill test to determine peak [Vdot]O(2) (mean = 40.3 +/- 6.3 ml . kg(-1) . min(-1)). Participants completed separate 30-min trials of moderate exercise (RPE of 13 on the Borg 6-20 scale) in random order on the treadmill: graded walking and ungraded jogging. Treadmill speed or grade was adjusted throughout the trial by the experimenter based on participant responses to maintain an RPE of 13. The jogging trial produced a significantly higher heart rate (161 +/- 18 vs. 142 +/- 24 beats . min(-1)) and [Vdot]O(2) (7.4 +/- 1.8 vs. 5.8 +/- 1.5 METs) (P < 0.01) than the walking trial. Treadmill grade decreased significantly during the walking trial (11.1 +/- 2.3% to 10.0 +/- 2.2%; P < 0.01), but treadmill speed did not change significantly during the jogging trial (5.2 +/- 1.0 miles . h(-1) to 5.0 +/- 0.9 miles . h(-1)) (P > 0.05), in an effort to maintain constant RPE. These findings provide evidence that similar perceptions of effort during graded walking and ungraded jogging do not produce similar cardiovascular and metabolic responses. The results indicate that, for a given prescribed perceived effort, jogging provides a greater stimulus for fitness benefits and caloric expenditure.