Supervised exercise training improves endothelial function in COPD patients: a method to reduce cardiovascular risk?

Supervised exercise training is key to health improvement in chronic obstructive pulmonary disease patients https://bit.ly/2AdfKvb.

Listening to music while running alters ground reaction forces: a study of acute exposure to varying speed and loudness levels in young women and men.

PURPOSE: Music listening while running enhances physiological and psychological features, resulting in a more enjoyable experience. The possible influence of music on ground reaction forces (GRF) during running, however, is unknown. Considering the 'distracting' role of music on runner's attention, we hypothesized that music would cover foot impacts against the ground. This study verified such hypothesis by testing the effects of different music volumes while running at different velocities. METHODS: Fifty fit volunteers (F:M = 22:8; 23 ± 2 years) performed 2-min running stints over 3 random conditions (80-dB, 85-dB music; 'no music'), at 3 velocities (8, 10, 12 km/h). Participants ran on a sensorized treadmill that recorded GRF during all experiments. RESULTS: Listening to 85-dB music resulted in greater GRF at 8 (p = 0.0005) and 10 km/h (p = 0.04) but not 12 km/h (p = 0.35) and not with 80-dB volume. Gender-based analyses revealed significant Condition × gender interactions only for 85-dB music vs. 'no music'. Bonferroni-adjusted comparisons revealed significant music-induced increases in GRF only in men at 8 km/h (+ 4.1 kg/cm2, p < 0.0005; women: + 0.8 kg/cm2, p = 0.47) and 10 km/h (+ 3.3 kg/cm2, p = 0.004; women: + 0.8 kg/cm2, p = 0.51) but not at 12 km/h. CONCLUSION: In active men, listening to loud music while running results in increased GRF, whereas no effect was observed in women. The lack of music effect in women may be related to structural factors, such as larger hip width-to-femoral length ratio, possibly resulting in different loading patterns. The present preliminary findings introduce high-volume music listening as a new potential risk factor for injury in young runners.

Home-Based, Moderate-Intensity Exercise Training Using a Metronome Improves the Breathing Pattern and Oxygen Saturation During Exercise in Patients With COPD.

PURPOSE: One of the well-known but less-investigated effects of pulmonary rehabilitation in patients with chronic obstructive pulmonary disease (COPD) is the change in breathing pattern toward a more efficient one (higher tidal volume [VT], lower breathing frequency). Evidence suggests this change can be obtained only with supervised, high-intensity exercise training (ExTr). However, some patients either do not have such programs available or are unable to exercise at higher intensity. We evaluated the effects of a 12-wk, moderate-intensity, home-monitored ExTr program using a metronome on the breathing pattern, oxygen saturation (SpO2), and dyspnea during exercise in patients with COPD. METHODS: Twenty-one patients with COPD (7 female, aged 64-85 yr) performed spirometry, incremental, and endurance walking tests (at 60% of maximal walking speed) on a treadmill before and after training. During the endurance test, patients were equipped with an instrument that continuously monitored ventilation ((Equation is included in full-text article.)E), breathing pattern, and SpO2. Patients trained at home for 12 wk, 30 min/d for at least 4 d/wk at moderate intensity. A metronome paced the walking speed. RESULTS: Sixteen patients completed the program. After training, a significant change was observed in breathing pattern (lower (Equation is included in full-text article.)E and (Equation is included in full-text article.)E/VT ratio; P < .001), a higher SpO2 (P < .001), and a lower dyspnea perception at the same work intensity (P < .01). The (Equation is included in full-text article.)E/VT ratio and SpO2 during exercise were significantly related (r = 0.56, P = .001). CONCLUSION: A change in breathing pattern towards more efficient ventilation can be obtained with a moderate, home-monitored ExTr program with a pace that is controlled by a metronome. Decreased (Equation is included in full-text article.)E/VT was associated with an improved SpO2 during exercise.

Moderating healthcare costs through an assisted physical activity programme.

BACKGROUND: During the last decades, physical inactivity has become increasingly important due to its effects on health; in the medical field, it has been highlighted that physical inactivity is one of the leading cause of death. Moreover, the increasing trend in a sedentary lifestyle has also led to economic concerns; for this reason, the need to develop healthcare programmes to raise awareness of the benefits of physical exercise among the global population has arisen. OBJECTIVE: This paper analyses the relationship between moderate physical activity, cost of pharmaceuticals and health services utilization with regard to a primary care community programme based on moderate exercise intervention. The study highlights the effect of an exercise programme for people in sheltered accommodation in terms of effects on their quality of life and in terms of economic sustainability. METHODOLOGY: A randomized controlled trial of an exercise programme was designed. A total of 150 patients were randomized in two groups. The intervention group was recruited from Centro Esercizio Vita whereas the participants of the control group were recruited from general practitioners. RESULTS: At 9 months after randomization, the exercise-based group presented a lower average cost for drugs (p-value 0.039), an overall better health status perception (p-value 0.0019) and accessed general practitioners less frequently (p-value 0.058). CONCLUSIONS: Our study shows that assisted physical activity practiced on the basis of an exercise programme, over a period of nine months, has overall positive consequences in terms of reduction in health expenditure and quality of life.

Residence at Moderate Versus Low Altitude Is Effective at Maintaining Higher Oxygen Saturation During Exercise and Reducing Acute Mountain Sickness Following Fast Ascent to 4559 m.

OBJECTIVE: To continuously monitor oxygen saturation (SpO2) by pulse oximeter and assess the development of acute mountain sickness (AMS) using the Lake Louise Score (LLS) during ascent from 1154 to 4559 m in 2 groups of subjects: 10 moderate-altitude residents (MAR; ≥1000-≤2500 m) and 34 low-altitude residents (LAR). MAR are reported to have a lower incidence of AMS during ascent to higher altitudes compared with LAR. Whether this is related to higher SpO2 is still open to debate. METHODS: Seventy subjects were recruited; 24-hour SpO2 monitoring with finger pulse oximetry was performed. All subjects rode a cable car from 1154 to 3275 m and then climbed to 3647 m, where 60 subjects (LAR) overnighted. The second day, 34/60 LAR reached the highest altitude. Ten subjects who lived permanently at 1100 to 1400 m (MAR) climbed directly to 4559 m without an overnight stop. RESULTS: One LAR was excluded from the analysis because he performed a preacclimatization. We compared data of 10 MAR with data of 33 LAR who reached 4559 m. Two MAR had an LLS of 3, and 8 scored <3. Six LAR had an LLS of 3 to 4, 8 scored ≥5, and 19 scored <3. SpO2 monitoring showed higher mean SpO2 in MAR during ascent above 3600 m compared with LAR (MAR, 79±4% vs LAR, 76±5%; analysis of variance, P = .03). CONCLUSIONS: The results of this preliminary study suggest that residence at moderate altitude allows maintenance of higher SpO2 and reduces risk of developing AMS during rapid ascent to higher altitude.

Respiratory muscle impairment in dialysis patients: can minimal dose of exercise limit the damage? A Preliminary study in a sample of patients enrolled in the EXCITE trial.

AIM: Skeletal muscle atrophy and dysfunction with associated weakness may involve the respiratory muscles of dialysis patients. We evaluated the effect of moderate-intensity exercise on lung function and respiratory muscle strength. METHODS: Fifty-nine patients (25 F, aged 65 ± 13 years) from two centers participating in the multicenter randomized clinical trial EXerCise Introduction To Enhance Performance in Dialysis (EXCITE) were studied. Subjects were randomized into a prescribed exercise group (E), wherein subjects performed two 10-min walking sessions every second day at an intensity below the self-selected speed, or a control group (C) with usual care. Physical performance was assessed by the 6-min walk test (6MWT). Patient lung function and respiratory muscle strength were evaluated by spirometry and maximal inspiratory pressure (MIP), respectively. RESULTS: Forty-two patients (14 F) completed the study. At baseline, the groups did not differ in any parameters. In total, 7 patients (4 in E; 3 in C) showed an obstructive pattern. The pulmonary function parameters were significantly correlated with 6MWT but not with any biochemical measurements. Group E safely performed the exercise program. At follow-up, the spirometry parameters did not change in either group. A deterioration of MIP (-7 %; p = 0.008) was observed in group C, but not in group E (+3.3 %, p = ns). In E, an increase of 6MWT was also found (+12 vs. 0 % in C; p = 0.038). CONCLUSION: In dialysis patients, a minimal dose of structured exercise improved physical capacity and maintained a stable respiratory muscle function, in contrast to the control group where it worsened.

Heart rate variability during sleep at high altitude: effect of periodic breathing.

BACKGROUND: Heart rate variability (HRV) during sleep in normal subjects at high altitude shows a decrease in parasympathetic tone associated with an increase in the sympathetic one, which tends to be reversed with acclimatization. However, periodic breathing (PB) during sleep may influence this effect detected by HRV spectral analysis. PURPOSE: The aim of our study was to investigate HRV during sleep periodic breathing (PB) at high altitude in normal subjects at two different times of acclimatization, i.e., two different levels of hypoxemia. METHODS: Recordings of six healthy climbers (aged between 33 and 40 years), at sea level (SL) and at Everest North Base Camp (5180 m), during the first (BC1) and the tenth (BC2) overnight unattended polygraphy, were analyzed. PB was commonplace in all subjects at high altitude to a variable extent. At SL and at BC1 and BC2, HRV was evaluated overnight and separately during clear regular breathing (RB) and PB. RESULTS: A mean overnight beat-by-beat series interval (RR) reduction at acute environmental hypoxic exposure that resumed to SL values after 10-day sojourn was observed. This reduction was mostly due to RR during RB, while during PB, RR values were not different from SL. Higher peaks of tidal volume were associated with higher HRV. CONCLUSIONS: The present study shows that in healthy subjects, PB with central apneas increases the amplitude of RR oscillations, and these oscillations are tightly related to respiratory amplitude. Oxygenation does not influence this phenomenon. Therefore, oscillations in ventilation itself should be taken into account when investigating HRV.

Respiratory muscle training with normocapnic hyperpnea improves ventilatory pattern and thoracoabdominal coordination, and reduces oxygen desaturation during endurance exercise testing in COPD patients.

BACKGROUND: Few data are available about the effects of respiratory muscle training with normocapnic hyperpnea (NH) in COPD. The aim is to evaluate the effects of 4 weeks of NH (Spirotiger(®)) on ventilatory pattern, exercise capacity, and quality of life (QoL) in COPD patients. METHODS: Twenty-six COPD patients (three females), ages 49-82 years, were included in this study. Spirometry and maximal inspiratory pressure, St George Respiratory Questionnaire, 6-minute walk test, and symptom-limited endurance exercise test (endurance test to the limit of tolerance [tLim]) at 75%-80% of peak work rate up to a Borg Score of 8-9/10 were performed before and after NH. Patients were equipped with ambulatory inductive plethysmography (LifeShirt(®)) to evaluate ventilatory pattern and thoracoabdominal coordination (phase angle [PhA]) during tLim. After four supervised sessions, subjects trained at home for 4 weeks - 10 minutes twice a day at 50% of maximal voluntary ventilation. The workload was adjusted during the training period to maintain a Borg Score of 5-6/10. RESULTS: Twenty subjects completed the study. After NH, maximal inspiratory pressure significantly increased (81.5±31.6 vs 91.8±30.6 cmH2O, P<0.01); exercise endurance time (+150 seconds, P=0.04), 6-minute walk test (+30 meters, P=0.03), and QoL (-8, P<0.01) all increased. During tLim, the ventilatory pattern changed significantly (lower ventilation, lower respiratory rate, higher tidal volume); oxygen desaturation, PhA, and dyspnea Borg Score were lower for the same work intensity (P<0.01, P=0.02, and P<0.01, respectively; one-way ANOVA). The improvement in tidal volume and oxygen saturation after NH were significantly related (R (2)=0.65, P<0.01). CONCLUSION: As expected, NH improves inspiratory muscle performance, exercise capacity, and QoL. New results are significant change in ventilatory pattern, which improves oxygen saturation, and an improvement in thoracoabdominal coordination (lower PhA). These two facts could explain the reduced dyspnea during the endurance test. All these results together may play a role in improving exercise capacity after NH training.

Long-term monitoring of oxygen saturation at altitude can be useful in predicting the subsequent development of moderate-to-severe acute mountain sickness.

OBJECTIVE: The use of pulse oximetry (Spo2) to identify subjects susceptible to acute mountain sickness (AMS) is the subject of debate. To obtain more reliable data, we monitored Spo2 for 24 hours at altitude to investigate the ability to predict impending AMS. METHODS: The study was conducted during the climb from Alagna (1154 m) to Capanna Regina Margherita (4559 m), with an overnight stay in Capanna Gnifetti (3647 m). Sixty subjects (11 women) were recruited. Each subject was fitted with a 24-hour recording finger pulse oximeter. The subjects rode a cable car to 3275 m and climbed to 3647 m, where they spent the night. RESULTS: In the morning, 24 subjects (6 women) had a Lake Louise Questionnaire score (LLS) ≥ 3 (AMS(+)), and 15 subjects (4 women) exhibited moderate-to-severe disease (LLS ≥ 5 = AMS(++)). At Alagna, Spo2 did not differ between the AMS(-) and AMS(+) subjects. At higher stations, all AMS(+) subjects exhibited a significantly lower Spo2 than did the AMS(-) subjects: at 3275 m, 85.4% vs 87.7%; resting at 3647 m, 84.5% vs 86.4%. The receiver operating characteristics curve analysis resulted in a rather poor discrimination between the AMS(-) subjects and all of the AMS(+) subjects. With the cutoff LLS ≥ 5, the sensitivity was 86.67%, the specificity was 82.25%, and the area under the curve was 0.88 (P < .0001) for Spo2 ≤ 84% at 3647 m. CONCLUSIONS: We conclude that AMS(+) subjects exhibit a more severe and prolonged oxygen desaturation than do AMS(-) subjects starting from the beginning of altitude exposure, but the predictive power of Spo2 is accurate only for AMS(++).

Periodic breathing, arterial oxyhemoglobin saturation, and heart rate during sleep at high altitude.

The aim of this study was to investigate the effects of acclimatization to high altitude on periodic breathing (PB), arterial oxygen saturation (Sao(2)), and heart rate (HR). Nine male elite climbers, age 24-52 years underwent overnight cardiorespiratory monitoring at sea level and at Everest North Base Camp (5180 m), during the first (BC1) and the tenth (BC2) nights. PB was commonplace in all subjects at high altitude. PB cycle duration increased (p<0.0001) from BC1 (21.7±1.9 s) to BC2 (26.7±2.1 s). Mean Sao(2) from BC1 to BC2, significantly increased during wakefulness (77.4±3.4% vs. 82.5±2.8%; p<0.001) and during sleep regular breathing (73.3±3.8% vs. 77.8±2.9%; p=0.022). During PB, mean higher Sao(2) was 75.3±3.6% at BC1 and 82.4±2.9% at BC2 (p<0.001); mean lower Sao(2) was 68.2±4.0% at BC1 and 74.5±4.3% at BC2 (p<0.01). During PB, mean higher HR was 72.4±8.8 b/min at BC1 and 63.3±6.0 b/min at BC2 (p<0.0002); mean lower HR were 53.6±7.5% at BC1 and 43.6±7.3% at BC2 (p<0.0001). The mean Sao(2) during PB compared with Sao(2) at night without PB was unchanged. Acclimatization to high altitude resulted in an overall increase in Sao(2) along with an increase in the PB cycle duration and a decrease in HR.

Does thoracic pump influence the cerebral venous return?

We assessed the hemodynamic effects induced by the thoracic pump in the intra- and extracranial veins of the cerebral venous system on healthy volunteers. Activation of the thoracic pump was standardized among subjects by setting the deep inspiration at 70% of individual vital capacity. Peak velocity (PV), time average velocity (TAV), vein area (VA), and flow quantification (Q) were assessed by means of echo color Doppler in supine posture. Deep respiration significantly increases PV, TAV, and Q, but it is limited to the extracranial veins. To the contrary, no significant hemodynamic changes were recorded at the level of the intracranial venous network. Moreover, at rest TAV in the jugular veins was significantly correlated with Q of the intracranial veins. We conclude that the modulation of the atmospheric pressure operated by the thoracic pump significantly modifies the hemodynamics of the jugular veins and of the reservoir of the neck and facial veins, with no effect on the vein network of the intracranial compartment.

A simple method for home exercise training in patients with chronic obstructive pulmonary disease: one-year study.

PURPOSE: The success of long-term exercise training (ExT) programs resides in the integration between exercise prescription and patient compliance with home training. One of the crucial issues for the patients is the understanding of appropriate exercise intensity. We compared 2 methods of home ExT, based on walking. METHODS: Forty-seven patients with chronic obstructive pulmonary disease were recruited and underwent respiratory function, exercise capacity evaluation with a 6-minute walk test, and treadmill tests. Physical activity was monitored by a multisensor Armband (SenseWear, Body Media, Pittsburgh, PA). Patients were randomly assigned to 2 different home training methods and assessed again after 6 and 12 months; group A1: speed walking paced by a metronome, and group A2: walking a known distance in a fixed time. RESULTS: Thirty-six patients completed the study. All subjects showed a significant improvement in the 6-minute walk test after 1 year but the improvement was higher in A1 than in A2 (P < .05). Physical activity levels were significantly higher at T12 versus baseline only in group A1 (P < .05). CONCLUSIONS: The use of a metronome to maintain the rate of walking during home ExT seems to be beneficial, allowing patients to achieve and sustain the optimal exercise intensity, and resulting in greater improvement compared to simply using a fixed time interval exercise.

The hypoxic profile during trekking to the Pyramid Laboratory.

UNLABELLED: The oxygen saturation values reported in the high altitude literature are usually taken during a few minutes of measurement either at rest or during exercise. We aimed to investigate the daily hypoxic profile by monitoring oxygen saturation for 24 h in 8 lowlanders (4 females, ages 26 to 59) during trekking from Lukla (2850 m) to the Pyramid Laboratory (5050 m). Oxygen saturation was measured (1) daily at each altitude (sm), (2) for 24-h during ascent to 3500 m, 4200 m, and on day 1 at 5050 m (lm), and (3) during a standardized exercise (em). RESULTS: (1) the sm and lm values were 90.9% (+/-0.5) and 86.4% (+/-1.1) at 3500 m; 85.2%(+/-1.1), and 80% (+/-1.9) at 4200 m; 83.8%(+/-1) and 77% (+/-1.7) at 5050 m (p < or = 0.05); (2) the daily time spent with oxygen saturation < or =90% was 56.5% at 3500 m, 81% at 4200 m, and 95.5% at 5050 m; (3) during exercise, oxygen saturation decreased by 10.58%, 13.43%, and 11.24% at 3500, 4200, and 5050 m, respectively. In conclusion, our data show that the level of hypoxemia during trekking at altitude is more severe than expected on the basis of a short evaluation at rest and should be taken into account.

Efficacy and tolerability of yoga breathing in patients with chronic obstructive pulmonary disease: a pilot study.

PURPOSE: Yoga-derived breathing has been reported to improve gas exchange in patients with chronic heart failure and in participants exposed to high-altitude hypoxia. We investigated the tolerability and effect of yoga breathing on ventilatory pattern and oxygenation in patients with chronic obstructive pulmonary disease (COPD). METHODS: Patients with COPD (N = 11, 3 women) without previous yoga practice and taking only short-acting beta2-adrenergic blocking drugs were enrolled. Ventilatory pattern and oxygen saturation were monitored by means of inductive plethysmography during 30-minute spontaneous breathing at rest (sb) and during a 30-minute yoga lesson (y). During the yoga lesson, the patients were requested to mobilize in sequence the diaphragm, lower chest, and upper chest adopting a slower and deeper breathing. We evaluated oxygen saturation (SaO2%), tidal volume (VT), minute ventilation (E), respiratory rate (i>f), inspiratory time, total breath time, fractional inspiratory time, an index of thoracoabdominal coordination, and an index of rapid shallow breathing. Changes in dyspnea during the yoga lesson were assessed with the Borg scale. RESULTS: During the yoga lesson, data showed the adoption of a deeper and slower breathing pattern (VTsb L 0.54[0.04], VTy L 0.74[0.08], P = .01; i>fsb 20.8[1.3], i>fy 13.8[0.2], P = .001) and a significant improvement in SaO2% with no change in E (SaO2%sb 91.5%[1.13], SaO2%y 93.5%[0.99], P = .02; Esb L/min 11.2[1.1], Ey L/min 10.2[0.9]). All the participants reported to be comfortable during the yoga lesson, with no increase in dyspnea index. CONCLUSION: We conclude that short-term training in yoga is well tolerated and induces favorable respiratory changes in patients with COPD.

Relationship between individual ventilatory response and acute renal water excretion at high altitude.

We tested the hypothesis that the individual ventilatory adaptation to high altitude (HA, 5050 m) may influence renal water excretion in response to water loading. In 8 healthy humans (33+/-4 S.D. years) we studied, at sea level (SL) and at HA, resting ventilation (VE), arterial oxygen saturation (SpO2), urinary output after water loading (WL, 20 mL/kg), and total body water (TBW). Ventilatory response to HA was defined as the difference in resting VE over SpO2 (DeltaVE/DeltaSpO2) from SL to HA. At HA, a significant increase in urinary volume after the first hour from WL (%WLt0-60) was observed. Significant correlations were found between DeltaVE/DeltaSpO2 versus %WLt0-60 at HA and versus changes in TBW, from SL to HA. In conclusion, in healthy subjects the ventilatory response to HA influences water balance and correlates with kidney response to WL. A higher ventilatory response at HA, allowing a more efficient water renal handling, is likely to be a protective mechanisms from altitude illness.