Hemodynamic responses during and after multiple sets of stretching exercises performed with and without the Valsalva maneuver

Abstract

OBJECTIVE:This study investigated the acute hemodynamic responses to multiple sets of passive stretching exercises performed with and without the Valsalva maneuver.METHODS:Fifteen healthy men aged 21 to 29 years with poor flexibility performed stretching protocols comprising 10 sets of maximal passive unilateral hip flexion, sustained for 30 seconds with equal intervals between sets. Protocols without and with the Valsalva maneuver were applied in a random counterbalanced order, separated by 48-hour intervals. Hemodynamic responses were measured by photoplethysmography pre-exercise, during the stretching sets, and post-exercise.RESULTS:The effects of stretching sets on systolic and diastolic blood pressure were cumulative until the fourth set in protocols performed with and without the Valsalva maneuver. The heart rate and rate pressure product increased in both protocols, but no additive effect was observed due to the number of sets. Hemodynamic responses were always higher when stretching was performed with the Valsalva maneuver, causing an additional elevation in the rate pressure product.CONCLUSIONS:Multiple sets of unilateral hip flexion stretching significantly increased blood pressure, heart rate, and rate pressure product values. A cumulative effect of the number of sets occurred only for systolic and diastolic blood pressure, at least in the initial sets of the stretching protocols. The performance of the Valsalva maneuver intensified all hemodynamic responses, which resulted in significant increases in cardiac work during stretching exercises.

The influence of the order between resistance and stretching exercises on the hemodynamic response

“…Therefore, our results are highly relevant, particularly because the literature on this topic is scarce. The inclusion of stretching exercises concurrent with RT noticeably promoted an increased HR and an increased RPP after the end of the session, corroborating the findings of Lima, Farinatti, Rubini, Silva, and Monteiro (2015). Stretching generates lower neural activation, which is associated with lower passive muscular tension (stiffness), rendering the subsequent exercise more intense, which could have caused metabolic compensation marked by an increase in HR and RPP values, according to Fowles, Sale, and MacDougall (2000).…”

Does the combination of resistance training and stretching increase cardiac overload?

“…As previous studies have indicated 5,37, cardiac load is increased by stretching exercises alone. Consequently, when the participants performed SS in combination with RT at 80% (the demand is even higher), the results that were obtained were expected.…”

“…Finally, the values between training sets would be of great value to aid in the interpretation of the present results. Thus, we emphasize the importance of new studies with similar designs, such as those performed by Farinatti et al 37 and Lima et al 5, to analyze the data between training sets and exercises.…”

“…Furthermore, Costa et al 4 suggested that stretching may increase the risk of injury because it can reduce force and generate muscular imbalances. Stretching may provide neural and/or structural modifications, reflecting changes in neuromuscular performance, as well as in the behavior of physiological variables 5,6.…”

“…Lima et al 5 examined the cardiovascular effects of stretching using the static stretching (SS) method, and they reported that SS increased heart overload by raising the heart rate (HR) (by approximately 20 bpm -1 ) and rate pressure product (RPP) (by approximately 5000 mmHg.bpm -1 ). In addition, previous studies 6-8 have found that pre-exercise SS diminishes the performance of force and may lower the oxygen supply to the stretched muscle 9,10.…”