Aim: Walking is a popular type of physical activity in individuals with schizophrenia – yet the benefits remain unclear. The aim of this review was to investigate if walking can a) reduce weight and b) have a positive influence on other health parameters in individuals (aged 16 years and over) with schizophrenia spectrum disorders in in- or outpatient settings. Methods: A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyse (PRISMA) statement was conducted. Major electronic databases were searched from inception to January 2014. Articles were eligible that: considered the effect of a walking intervention; had included at least 75% of the intervention programme as walking rather than another type of physical activity; considered patients formally diagnosed using standard criteria of schizophrenia or schizo-affective spectrum disorders; and used outcome measures that captured the patient's bio-psychosocial health. Two independent authors conducted the searches, extracted data and completed methodological quality and risk of bias assessment. Results: A total of 10 trials from three countries were included (n=339). Selection, detection and performance biases were identified consistently within the research. There is some evidence to suggest walking interventions may benefit an individual's weight, specifically resulting in small reduction in body mass index or body fat in the short term. Evidence for other health outcomes was limited but no adverse events were reported and walking appears to be safe. The data did not provide enough information for a meta-analysis to be conducted. Conclusion: Walking is a popular and safe form of physical activity among individuals with schizophrenia spectrum disorders. No harmful effects were reported and small, short-term weight reduction was identified. However, the results may not be clinically meaningful and should be viewed with caution due to the medium-to-high risk of bias. The broader benefits of walking are yet to be established. Despite the methodological limitations in the literature, walking should be encouraged in clinical practice but clinicians may need to adopt motivational strategies to increase adherence.

The current study investigated whether ambient heat augments the inflammatory and post-exercise hepcidin response in women, and if menstrual phase and/or self-pacing modulate these physiological effects. Eight trained females (age: 37±7 y; VO2max: 46±7 mL∙kg-1∙min-1; peak power output: 4.5±0.8 W∙kg-1) underwent 20 min of fixed-intensity cycling (100 and 125 W) followed by a 30-min work trial (≈75% VO2max) in a moderate (MOD: 20±1 °C, 53±8% relative humidity) and warm-humid (WARM: 32±0 °C, 75±3% relative humidity) environment in both their early follicular (days 5±2) and mid-luteal (days 21±3) phases. Mean power output was 5±4 W higher in MOD than in WARM (p=0.02) such that the difference in core temperature rise was limited between environments (-0.29±0.18 °C in MOD, p<0.01). IL-6 and hepcidin both increased post-exercise (198% and 38%, respectively), however, neither were affected by ambient temperature or menstrual phase (all p>0.15). Multiple regression analysis demonstrated that the IL-6 response to exercise was explained by leukocyte and platelet count (r2=0.72, p<0.01) and the hepcidin response to exercise was explained by serum iron and ferritin (r2=0.62, p<0.01). During exercise participants almost matched their fluid loss (0.48±0.18 kg·h-1) with water intake (0.35±0.15 L·h-1) such that changes in body mass (-0.3±0.3%) and serum osmolality (0.5±2.0 mOsm·kg-1) were minimal or negligible, indicating a behavioral fluid-regulatory response. These results indicate that trained, iron sufficient women suffer no detriment to their iron regulation in response to exercise with acute ambient heat stress or between menstrual phases on account of a performance-physiological trade-off.

This study examined the effect of mouth rinsing during endurance cycling in a hot humid environment (32 °C and 75% relative humidity) on athletes in the Ramadan fasted state. Nine trained adolescent male cyclists completed 3 trials that consisted of a carbohydrate mouth-rinse (CMR), a placebo mouth-rinse (PMR), and a no-rinse (NOR) trial during the last 2 weeks of Ramadan. Each trial consisted of a preloading cycle at 65% peak rate of oxygen consumption for 30 min followed by a 10-km time trial (TT10 km) under hot humid condition. During the CMR and PMR trials, each cyclist rinsed his mouth with 25 mL of the solution for 5 s before expectorating the solution pre-exercise, after 5, 15, and 25 min of the preloading cycle, and 15 s prior to the start of TT10 km. Time to complete the TT10 km was significantly faster in the CMR and PMR trials compared with the NOR trial (12.9 ± 1.7 and 12.6 ± 1.7 vs. 16.8 ± 1.6 min, respectively; p < 0.017). Ratings of perceived exertion taken at the end of the TT10 km was lower in both CMR and PMR trials compared with the NOR trial, although the difference was significant only between CMR and NOR (p < 0.05). In conclusion, mouth rinsing with either carbohydrate or placebo solution provided ergogenic benefits compared with a no-rinse condition on TT10 km performance in acute Ramadan fasted subjects during endurance cycling in a heat stress environment.

This study examined the thermoregulatory and circulatory responses, and exercise performance of trained distance runners during exercise in the heat (31°C) at varying relative humidity (RH). In a randomized order, 11 trained male distance runners performed 5 60 min steady-state runs at a speed eliciting 70% of VO2max in RH of 23, 43, 52, 61 and 71%. This was followed immediately with an incremental exercise test to volitional exhaustion. Core (Tre) and mean skin temperature (T¯sk), cardiac output (Q), heart rate (HR), and stroke volume (SV) were recorded at regular intervals. A significant (P = 0.003) main effect was detected for RH on mean body temperature (Tb), with a significantly higher Tb detected during steady-state exercise in the 61 and 71% RH compared to that in the 23% RH. During the steady-state exercise, no differences were detected in whole body sweat loss (P = 0.183). However, a significant main effect of RH was observed for HR and SV (P = 0.001 and 0.006, respectively) but not Q (P = 0.156). The time to exhaustion of the incremental exercise test was significantly reduced at 61 and 71% RH compared with 23% RH (P = 0.045 and 0.005, respectively). Despite an increase in dry heat loss, a greater thermoregulatory and circulatory stress was evident during steady-state exercise at 61 and 71% RH. This ultimately limits the capacity to perform the subsequent incremental exercise to exhaustion. This study highlighted that in a warm environment, the range of the prescriptive zone progressively narrows as RH increases.

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