Coordination-related changes in the rhythms of breathing and walking in humans

Coordination of the respiratory rhythm with the rhythm of limb movements has often been observed during rhythmical exercise (e.g. in locomotion). It is usually associated with changes in the respiratory time course, but not in the locomotor rhythm. Therefore, we hypothesised that in walking, the extent of coordination-related changes (CRC) in respiratory parameters would increase with closer coordination. With respect to the controversially discussed question of a possible energetic advantage due to coordination, we devoted particular interest to the CRC in oxygen uptake (V˙O₂). In addition, we investigated the incidence and the extent of CRC in the stepping rhythm. We examined 18 volunteers walking on a treadmill at three different workload levels, which were adjusted by altering either the velocity or slope of the treadmill. Each walking test was carried out twice, once with spontaneous breathing and once with breathing paced by a step-related acoustic signal to enhance the coordination between breathing and walking. No correlation was found between the CRC in the analysed parameters and the degree of coordination. However, the extent of CRC of ventilation and V˙O₂ decreased with increasing workload. With the transition to coordination, increases and decreases of V˙O₂ occurred about equally often. From this we conclude that energetic economisation in walking, as reflected by a reduction in V˙O₂, is rather a side-effect of coordination, and is probably due to a more precise regulation of the breathing pattern. The economisation was more pronounced at higher work loads than at lower work loads. Our results revealed that coordination is also associated with changes in the stepping rate, which occurred more frequently when the variability of breathing was restricted by acoustic pacing of the breathing rhythm. This finding suggests that the choice of walking rhythm is not completely free, but can be influenced by the breathing rhythm. CRC in the walking rhythm might contribute to the avoidance of excessive CRC in the respiratory time course, which would entail an inefficient breathing pattern and thus, an energetic disadvantage. Accepted: 29 March 2000     

Controversies in sleep-related breathing disorders

This review addresses some current controversies and issues of interest in sleep-related disorders of breathing. Abnormalities of respiratory control may influence the degree of obstructive sleep apnea but it is likely that abnormalities of pharyngeal size are of far greater significance. Central sleep apnea is a heterogeneous condition. Examples of all the causes one would postulate leading to cessation of drives to breathe do occur, hence appropriate therapies also vary. It is not yet known what aspect of, and how much, disordered breathing during sleep leads to morbidity, thus fixed definitions of normality are not helpful. Recurrent nocturnal asphyxia alone is unlikely to result in chronic respiratory failure. Associated diffuse airways obstruction or impaired respiratory muscle function is probably necessary before this complication arises. The recurent REM sleep-induced dips of Sao₂ in patients with chronic airways obstruction may be due to physiological inhibition of accessory muscles of respiration. This leads to considerable hypoventilation and recurrent activation of an intact, but displaced, hypoxic drive, resulting in the characteristic oscillations of Sao₂.     

大运动量训练对尿中内源性激素比值的影响

目的　本文对男女运动员晨尿中几对内源性激素的比值进行研究和探讨 ,用于确定正常变化值。同时研究大运动量训练对这些内源性雄性激素比值的影响 ,为反兴奋剂工作提供帮助。方法　均采用GC -MS法在美国产的HP5 890及HP5 971GC -MS上测定 ,用Sim方式进行检测 ,将测得的特征离子峰进行积分 ,以甲睾作为内标算出待测尿样的几类激素的浓度。结果　机体内源性雄性激素的比值 ,男性运动员尿中An/Etio ,5α/5 β ,T/ET均明显高于女运动员 (P <0 0 5 ) ,而 11An/ 11Etio则明显低于女性运动员 (P <0 0 5 )。尿中内源性雄性激素受运动训练的影响 ,其中T/ET改变最为明显 ,其次为 11-OHAn/ 11-OHEtio(P <0 0 5 ) ,且男性运动员的变化比女性运动员的变化更加明显。其它两组变化则不明显。结论　尿中几对内源性雄性激素的比值个体差异较大 ,且有明显的性别差异 ,同时受运动训练的影响     

呼吸过滤器临床应用进展

呼吸过滤器（breathing filter，BF）也称生物过滤器、热湿交换过滤器、人工鼻等，是一人类在呼吸回路中使用的过滤器，具有不同程度的生物滤过功能和加温保湿作用。近年BF已逐渐在临床推广使用，是作为机械通气（mechanical ventilation，MV）期间保护气道、降低呼吸回路微生物污染、保护肺功能等的重要措施，也是避免交叉感染和控制院内感染的主要手段。     

Comparison of manipulation and stabilization exercises in patients with sacroiliac joint dysfunction patients: A randomized clinical trial

Background

Manual therapy and exercise therapy are two common treatments for low back pain. Although their effects have been discussed in several studies, the superiority of one over the other for patients with sacroiliac joint dysfunction is still unclear.

Preliminary investigations into the effects of breathing retraining techniques on end-tidal carbon dioxide measures in patients with asthma and healthy volunteers during a single treatment session

Objectives

Preliminary investigations into the physiological effects of breathing retraining techniques in order to establish the feasibility of the proposed methodology, produce data for power calculations and determine the potential for future research in this area.

Design

Two preliminary, exploratory studies with an experimental design.

Setting

Research laboratories.

Participants

Study 1: 15 patients with mild to moderate asthma and nine healthy volunteers. Study 2: 15 healthy volunteers.

Interventions

Physiological data from asthma patients and healthy volunteers were recorded before, during and after a single session of slow breathing and breath holds. A separate group of healthy participants carried out the slow breathing technique with and without visual biofeedback.

Outcome measures

The primary outcome was end-tidal carbon dioxide (ETCO₂), and the secondary outcomes were respiratory rate, pulse rate, oxygen saturation and lung function.

Results

All groups showed an increase in ETCO₂ from baseline during slow breathing. Study 1 found a mean rise in ETCO₂ of 0.48 kPa [95% confidence interval (CI) 0.28-0.68] for healthy participants and 0.46 kPa (95% CI 0.29-0.63) for asthma patients. In healthy volunteers, ETCO₂ stayed above baseline for 5 minutes after the intervention. ETCO₂ rose minimally (mean 0.06 kPa) in both groups after breath holds. Study 2 found a mean rise in ETCO₂ of 0.35 kPa (95% CI 0.09-0.60) during slow breathing with visual feedback, and 0.36 kPa (95% CI 0.13-0.60) during slow breathing without visual feedback.

Conclusions

The results of these preliminary studies provide data to power larger studies. They suggest that ETCO₂ rises during slow breathing in both asthma patients and healthy volunteers, and that this effect may persist beyond the intervention itself in healthy volunteers. The use of visual biofeedback had no effect on ETCO₂ in healthy volunteers.     

骨质疏松治疗的新进展(二)

就促进骨形成药物、钙剂及维生素D、运动锻炼及外科手术治疗骨质疏松症的进展作一综述。     

应用皮格马利翁效应提高慢性阻塞性肺病患者呼吸功能锻炼的依从性

目的探讨应用皮格马利翁效应提高慢性阻塞性肺病患者呼吸功能锻炼的依从性效果。方法将105例慢性阻塞性肺病患者按住院号尾数奇数、偶数分组，观察组46例，对照组59例；对照组给予常规呼吸功能锻炼指导，观察组应用皮格马利翁效应实施呼吸功能锻炼指导；观察两组住院期间平均每次锻炼时间、锻炼时每分钟呼吸次数及出院1月时呼吸功能锻炼坚持率。结果观察组每次锻炼平均时间较对照组长、锻炼时每分钟呼吸次数较对照组少、出院1月时呼吸功能锻炼坚持率较对照组高，差异比较有统计学意义。结论应用皮格马利翁效应能提高慢性阻塞性肺病患者呼吸功能锻炼的依从性。     

Chronic pelvic pain: Pelvic floor problems, sacro-iliac dysfunction and the trigger point connection

The incidence of chronic pelvic pain (CPP) is widespread, with multiple potential aetiological features. There is evidence that CPP is relatively poorly understood, even by specialists in genitourinary dysfunction and disease, and certainly by the wider health care community. Recent research has suggested connections between chronic sacro-iliac restrictions/instability and a wide range of pelvic floor related problems, as well as breathing pattern dysfunction. In addition myofascial trigger points are reported to be commonly actively involved in the pain aspects of problems associated with these structures. Studies have also indicated that in many instances CPP is amenable to manual therapeutic approaches.It has been hypothesized that inadequate force closure may be a common aetiological feature, affecting both urethral and sacroiliac instability. This paper attempts to outline current research-based concepts linking these mechanisms and influences with pelvic pain and dysfunction, including variously interstitial cystitis, stress incontinence, dyspareunia, vulvodynia, prostatitis, prostatodynia, penile pain, sacroiliac dysfunction, myofascial trigger point activity, and respiratory disorders such as hyperventilation. Evidence-based therapeutic approaches suitable for application by physiotherapists, osteopaths and other manual practitioners and therapists are discussed.