Energy expenditure, physical activity, and body composition of ambulatory adults with hereditary neuromuscular disease

Abstract

Persons with neuromuscular disease (NMD) have progressive weakness and wasting of skeletal muscle, reduced fat-free mass, and increased fat mass relative to healthy control subjects. To test the hypothesis that resting energy expenditure (REE), estimated total daily energy expenditure (TEE), and physical activity patterns are altered in ambulatory adults with NMD, 26 adult men and women with slowly progressive NMD and 19 able-bodied control subjects similar in age and weight were evaluated. REE was measured after an overnight fast by indirect calorimetry, TEE by heart rate monitoring, and body composition by air-displacement plethysmography. REE was not significantly different between NMD and control subjects; however, TEE was significantly reduced in NMD subjects compared with control subjects, respectively (women: 7.8 +/- 1.5 compared with 10.5 +/- 2.8; men: 10.2 +/- 3.6 compared with 12.7 +/- 2.6 MJ/d; P < or = 0.01), indicating that NMD subjects expended less energy in physical activity than did control subjects. NMD subjects also tended toward an increased energy cost of physical activity, particularly at higher activity levels (P = 0.06). Multiple regression analysis indicated that for all subjects combined, adiposity was positively associated with age and TEE and negatively associated with time spent in the active heart rate range and fat-free mass (P < or = 0.0001). This relation did not differ between NMD and control subjects, nor did it differ between men and women. We hypothesize that because of their reduced physical activity and increased adiposity, persons with NMD may be at risk for developing secondary conditions such as cardiovascular disease, hypertension, and diabetes.

An exploratory study of physical activity and perceived barriers to exercise in ambulant people with neuromuscular disease compared with unaffected controls

“…Flex heart rate has been used in a previous study. 8 The results of our study, with flex heart rate being greater in neuromuscular disease participants, were consistent with that study. The definition of a reproducible flex heart rate to distinguish between resting and activity heart rate is problematic as it is based on the assumption that one discrete pulse point can provide a clear-cut physiological distinction between rest and exercise.…”

“…Participants with neuromuscular disease walked at 1.6, 2.5 and 3.2 km/h or 1.1, 1.8 and 2.4 km/h according to ability. This is consistent with a previous study, 8 allowing comparisons to be made. Heart rate was recorded and stored at 15-second intervals.…”

Functioning and disability in adults with myotonic dystrophy type 1

“…Low cardiorespiratory fitness was also found in 50% of the persons who performed the submaximal cycle ergometer test. Although the issue is sparsely studied, several authors have noted that persons with slowly progressive neuromuscular diseases such as DM1 risk developing secondary chronic conditions such as cardiovascular diseases and diabetes, due to reduced physical activity, a sedentary lifestyle and obesity [45,46]. Features of the metabolic syndrome, i.e.…”

Resting energy expenditure in Duchenne patients using home mechanical ventilation

“…In adult patients with various types of neuromuscular disease, including some DMD patients, MCCRORY et al [26] found a preserved REE but a reduced total daily energy expenditure. In patients with myotonic dystrophy, JOSEFOWICZ et al [24] reported a reduction in REE expressed as a function of body surface area, but an augmentation when expressed as a function of FFM.…”

“…Patients in the current study, however, were adults, had a dramatically reduced muscle mass and had patent chronic respiratory insufficiency. In the studies of MCCRORY et al [26], HANKARD et al [27], and ZANARDI et al [28], the patients were not mechanically ventilated and had a relatively preserved FFM. In this regard, it is important to keep in mind the data provided by ZURLO et al [29], showing that skeletal muscle can account for up to 20% of REE, and the data of KAYSER [30] showing that skeletal muscle is responsible for 25% of V9O 2 of the body.…”