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

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.

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

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. .

Flexibility of the elderly after one-year practice of yoga and calisthenics.

Flexibility training responses to distinct stretching techniques are not well defined, especially in the elderly. This study compared the flexibility of elderly individuals before and after having practiced hatha yoga and calisthenics for 1 year (52 weeks), at least 3 times/week. Sixty-six subjects (12 men) measured and assigned to 3 groups: control (n = 24, age = 67.7±6.9 years), hatha yoga (n = 22, age = 61.2±4.8 years), and calisthenics (n = 20, age = 69.0±5.8 years). The maximal range of passive motion of 13 movements in 7 joints was assessed by the Flexitest, comparing the range obtained with standard charts representing each arc of movement on a discontinuous and non-dimensional scale from 0 to 4. Results of individual movements were summed to define 4 indexes (ankle+knee, hip+trunk, wrist+elbow, and shoulder) and total flexibility (Flexindex). Results showed significant increases of total flexibility in the hatha yoga group (by 22.5 points) and the calisthenics group (by 5.8 points) (p < 0.01 for each) and a decrease in the control group (by 2.1 points) (p < 0.01) after one year of intervention. Between-group comparison showed that increases in the hatha yoga group were greater than in the calisthenics group for most flexibility indexes, particularly the overall flexibility (p <0.05). In conclusion, the practice of hatha yoga (i.e., slow/passive movements) was more effective in improving flexibility compared to calisthenics (i.e., fast/dynamic movements), but calisthenics was able to prevent flexibility losses observed in sedentary elderly subjects.

Immediate effect of static and proprioceptive neuromuscular facilitation stretching on hip adductor flexibility in female ballet dancers.

The aim of the present study was to investigate the immediate effects of static and proprioceptive neuromuscular facilitation (PNF) stretching on the flexibility of hip adductors in female ballet dancers. Forty-five subjects (age: 28.5 ± 8.0 years; minimum two years of ballet training) were randomly assigned to three groups: PNF (contract-release technique), Static, and Control. Subjects in the PNF and Static groups performed four sets of 30 second stretching with an interval of 30 seconds between sets. The control group stayed at rest for the same time spent by the PNF and Static groups during the stretching sessions. Maximal range of motion was measured before and immediately after the experimental and control protocols in all groups. The results indicated significant differences between pre- and post-stretching flexibility in both PNF and Static groups (p < 0.0001; effect size = 0.24 and 0.39, respectively), whereas no change was identified in the Control group (p = 0.265). However, no differences in post-exercise flexibility were found between PNF and Static groups (p = 0.235). It is concluded that static and PNF stretching methods provoked similar post-exercise acute effects on the maximal range of motion of hip adductors in highly flexible female ballet dancers.

The effects of stretching on strength performance.

Strength and flexibility are common components of exercise programmes; however, it is not clear how best to include both of these elements in a single training programme. It is common practice among athletes, coaches and recreational exercisers to perform a stretching routine before a strength training session. Stretching exercises are regularly recommended, even in many textbooks, with the claimed purpose of preventing injury and muscle soreness, or even enhancing performance. However, as highlighted in recent review articles, this recommendation lacks scientific evidence. Thus, the purpose of the present review is to determine the acute and chronic effects of stretching on strength performance, together with the underlying mechanisms. Although most studies have found acute decreases in strength following stretching, and that such decreases seem to be more prominent the longer the stretching protocol, the number of exercises and sets, and the duration of each set have, in general, exceeded the ranges normally recommended in the literature. Consequently, the duration of the stimuli were excessively long compared with common practice, thus making evident the need for further studies. In addition, when recommending flexibility exercises, one should consider other underlying issues, such as the safety of the participants, possible increases in injury risks and the unnecessary time expenditure. Many mechanisms underlying stretching exercises still demand investigation so that links between the observed effects, their causes and the consequences may be constructed.