Type 1 diabetes is a challenging condition to manage for various physiological and behavioural reasons. Regular exercise is important, but management of different forms of physical activity is particularly difficult for both the individual with type 1 diabetes and the health-care provider. People with type 1 diabetes tend to be at least as inactive as the general population, with a large percentage of individuals not maintaining a healthy body mass nor achieving the minimum amount of moderate to vigorous aerobic activity per week. Regular exercise can improve health and wellbeing, and can help individuals to achieve their target lipid profile, body composition, and fitness and glycaemic goals. However, several additional barriers to exercise can exist for a person with diabetes, including fear of hypoglycaemia, loss of glycaemic control, and inadequate knowledge around exercise management. This Review provides an up-to-date consensus on exercise management for individuals with type 1 diabetes who exercise regularly, including glucose targets for safe and effective exercise, and nutritional and insulin dose adjustments to protect against exercise-related glucose excursions.

It has been argued that minimization of metabolic-energy costs is a primary determinant of gait selection in terrestrial animals. This view is based predominantly on data from humans and horses, which have been shown to choose the most economical gait (walking, running, galloping) for any given speed. It is not certain whether a minimization of metabolic costs is associated with the selection of other prevalent forms of terrestrial gaits, such as grounded running (a widespread gait in birds). Using biomechanical and metabolic measurements of four ostriches moving on a treadmill over a range of speeds from 0.8 to 6.7 m s -1 , we reveal here that the selection of walking or grounded running at intermediate speeds also favours a reduction in the metabolic cost of locomotion. This gait transition is characterized by a shift in locomotor kinetics from an inverted-pendulum gait to a bouncing gait that lacks an aerial phase. By contrast, when the ostrich adopts an aerial-running gait at faster speeds, there are no abrupt transitions in mechanical parameters or in the metabolic cost of locomotion. These data suggest a continuum between grounded and aerial running, indicating that they belong to the same locomotor paradigm.

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OBJECTIVE -To compare the response of blood glucose levels to intermittent highintensity exercise (IHE) and moderate-intensity exercise (MOD) in individuals with type 1 diabetes. RESEARCH DESIGN AND METHODS-Seven healthy individuals with type 1 diabetes were tested on two separate occasions, during which either a 30-min MOD or IHE protocol was performed. MOD consisted of continuous exercise at 40% VO 2peak , while the IHE protocol involved a combination of continuous exercise at 40% VO 2peak interspersed with 4-s sprints performed every 2 min to simulate the activity patterns of team sports.RESULTS -Both exercise protocols resulted in a decline in blood glucose levels. However, the decline was greater with MOD (Ϫ4.4 Ϯ 1.2 mmol/l) compared with IHE (Ϫ2.9 Ϯ 0.8 mmol/l; P Ͻ 0.05), despite the performance of a greater amount of total work with IHE (P Ͻ 0.05). During 60 min of recovery from exercise, glucose levels remained higher in IHE compared with MOD (P Ͻ 0.05). Furthermore, glucose levels remained stable during recovery from IHE, while they continued to decrease after MOD (P Ͻ 0.05). The stabilization of blood glucose levels with IHE was associated with elevated levels of lactate, catecholamines, and growth hormone during early recovery from exercise (P Ͻ 0.05). There were no differences in free insulin, glucagon, cortisol, or free fatty acids between MOD and IHE.CONCLUSIONS -The decline in blood glucose levels is less with IHE compared with MOD during both exercise and recovery in individuals with type 1 diabetes. Diabetes Care 28:1289 -1294, 2005E xercise is generally recommended for individuals with type 1 diabetes for the same reasons as the rest of the population. That is, regular physical activity has physiological benefits, including improved physical work capacity, body composition, blood pressure, and blood lipid profile (1-3) and is associated with less risk of diabetes complications and mortality in individuals with type 1 diabetes (4). In addition, exercise has psychological benefits, including increased sense of well-being, quality of life, and ability to cope with stress (3). Particularly in children, participation in sports is an important recreational and social activity that benefits both social interaction and peer group assimilation (5).Unfortunately, participation in exercise can also increase the risk of experiencing hypoglycemia in individuals with type 1 diabetes, both during exercise (6,7) and for up to 31 h of recovery (8). Consequently, many individuals with type 1 diabetes feel negatively toward physical activity (9) and are discouraged from participating in sports and games by their parents, school staff, or physicians (10).Existing guidelines to minimize the risk of hypoglycemia associated with exercise are often general (11) and fail to take into account that different precautions are required for exercise of varying type, duration, and intensity. Specifically, there are no evidence-based guidelines for individuals wanting to participate in intermittent high-intensity exercise (IHE...

displacement of the lower limb necessary for steering the swinging limb clear of the stance limb and replaces what would otherwise require greater adduction/abduction and/or internal/external rotation, allowing for less complex joints, musculoskeletal geometry and neuromuscular control. Significant rotation about the joints' nonflexion/extension axes nevertheless occurs over the running stride. In particular, hip abduction and knee internal/external and varus/valgus motion may further facilitate limb clearance during the swing phase, and substantial non-flexion/extension movement at the knee is also observed during stance. Measurement of 3-D segment and joint motion in birds will be aided by the use of functionally determined axes of rotation rather than assumed axes, proving important when interpreting the biomechanics and motor control of avian bipedalism.