Patients with schizophrenia have impaired physical health. However, evidence of how skeletal muscle force‐generating capacity (FGC), a key component of functional performance, may contribute to the impairment is scarce. Thus, the aim of this study was to investigate the patient groups’ skeletal muscle FGC and its association with functional performance. Leg‐press FGC was assessed along with a battery of functional performance tests in 48 outpatients (28 men, 34 ± 10 years; 20 women, 36 ± 12 years) with schizophrenia spectrum disorder (ICD‐10, F20‐29), and compared with 48 healthy age‐ and gender‐matched references. Results revealed reduced one‐repetition maximum (1RM) in men (−19%, P < .01) and a trend toward reduction in women (−13%, P = .067). The ability to develop force rapidly was also impaired (men: −30%; women: −25%, both P < .01). Patients scored worse than healthy references on all physical performance tests (stair climbing: −63%; 30‐second sit‐to‐stand (30sSTS): −48%; six‐minute walk test (6MWT): −22%; walking efficiency: −14%; and unipedal stance eyes open: −20% and closed: −73%, all P < .01). 1RM correlated with 6MWT (r = .45), stair climbing (r = −.44), 30sSTS (r = .43), walking efficiency (r = .26), and stance eyes open (r = .33) and closed (r = .45), all P < .01. Rapid force development correlated with 6MWT (r = .54), stair climbing (r = −.49), 30sSTS (r = .45), walking efficiency (r = .26), and stance eyes open (r = .44) and closed (r = .51), all P < .01. In conclusion, skeletal muscle FGC and functional performance are reduced in patients with schizophrenia and should be recognized as important aspects of the patient groups’ impaired health. Resistance training aiming to improve these components should be considered an important part of clinical treatment.

Patients with schizophrenia are physically inactive and have high prevalence of cardiovascular disease (CVD). Peak oxygen uptake (V̇O2peak) is one of the strongest predictors for CVD, yet is rarely investigated in this patient population, and how V̇O2peak relates to other conventional CVD risk measures in this population is unclear. We measured treadmill V̇O2peak along with daily physical activity assessed by triaxial accelerometry, body mass index (BMI), waist circumference, blood pressure, lipid profiles, and glucose in 48 outpatients (28 men, 35 ± 10 (SD) years; 20 women, 35 ± 12 years), diagnosed with schizophrenia, schizotypal, or delusional disorders (ICD‐10; F20‐29). The patients were compared with 48 age‐ and sex‐matched healthy references (±2 years) and normative data from the population. V̇O2peak was 34.5 ± 8.7 mL/kg/min (men) and 26.4 ± 7.0 mL/kg/min (women), which was 27% and 30% lower than healthy references, respectively (both P < 0.01). V̇O2peak was not associated with daily physical activity in men while a weak association was seen in women (steps per day: r2 = 0.26; counts per minute: r2 = 0.25; P < 0.05). BMI (26.0 ± 6.1 kg/m2) revealed that patients were moderately overweight with a waist circumference of 103 ± 17 cm. Lipid‐ and glucose levels, and blood pressure were all within normative range. Our data advocate the utilization of V̇O2peak assessment for CVD risk profile determination in patients with schizophrenia. Daily physical activity was poorly and inconsistently related to V̇O2peak, suggesting increased daily physical activity might not translate into improved V̇O2peak and CVD risk reduction.

Patients with schizophrenia spectrum disorders have impaired skeletal muscle force‐generating capacity (FGC) of the lower extremities, that is, one repetition maximum (1RM) and rapid force development, and poor functional performance. We therefore investigated whether 12 weeks of maximal strength training (MST) could (a) restore FGC and functional performance to the level of healthy references, (b) increase patient activation and quality of life, and (c) explore associations between symptom severity, defined daily dose of medication, illness duration, level of patient activation, and improvements in FGC and functional performance. Forty‐eight outpatients were randomized to a training group (TG) or control group (CG). TG performed leg press MST 2 day/week at ~ 90% 1RM. The CG received two introductory training sessions and encouragement to train independently. Leg press 1RM, rapid force development, a battery of functional performance tests, Patient Activation Measure‐13, and 36‐Item Short Form Health Survey were tested. Healthy references performed baseline tests of FGC and functional performance. Thirty‐six patients completed the study (TG: 17, CG: 19). TG improved 1RM (28%) and rapid force development (20%, both P < .01) to a level similar to healthy references, while no change was apparent in the CG. TG’s improvement in rapid force development was negatively associated with defined daily dose of medication (r = −0.5, P = .05). Both TG and CG improved 30‐second sit‐to‐stand test performance (P < .05) which was associated with improved rapid force development (r = 0.6, P < .05). In conclusion, 12 weeks of MST restored patients’ lower extremity FGC to a level similar to healthy references and improved 30‐second sit‐to‐stand test performance.

It is known that the respiratory muscles have a significant increasing oxygen demand in line with hyperpnoea during whole-body endurance exercise and are susceptible to fatigue, in much the same way as locomotor muscles. The act of ventilation can itself be considered a form of exercise. The manipulation of respiratory load at near-maximal exercise alters leg blood flow significantly, demonstrating a competitive relationship between different skeletal muscle vascular beds to perfuse both sets of muscles adequately with a finite cardiac output. In recent years, the question has moved towards whether this effect exists during submaximal exercise, and the use of more direct measurements of respiratory muscle blood flow itself to confirm assumptions that uphold the concept. Evidence thus far has shown that there is a reciprocal effect on blood flow redistribution during ventilatory load manipulation observed at the respiratory muscles themselves and that the effect is observable during submaximal exercise, where active limb blood flow was reduced in conditions that simulated a high work of breathing. This has clinical applications for populations with respiratory disease and heart failure, where the work of breathing is remarkably high, even during submaximal efforts.

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