The hypothesis that biased symptom perception toward excessive symptoms is common when relatively normal chronic patients enter symptom-relating situations, irrespective of emotional variables, was tested in 19 women with severe asthma, 18 with somatization-like characteristics, and 18 controls. Each underwent three experimental conditions: mental stress, resting, and physical exercise. Each condition included three breathing conditions: breathing normally, normal compressed air, and 5.5% CO2-enriched compressed air. Results yielded no group differences in physiological measures, e.g. elevated CO2 in exhaled air (end-tidal partial pressure of CO2, PetCO2), or lung function. Asthma patients experienced more breathlessness, and somatization-like participants more breathlessness, miscellaneous symptoms, and subjective stress than controls. Although these differences suggested acquired biased symptom perception, as it turned out, breathlessness in asthmatics was more influenced by PetCO2 and less by subjective stress compared to controls. Likewise, breathlessness in somatization-like participants was similarly influenced by PetCO2 and subjective stress compared to controls, and miscellaneous symptoms were even more influenced by PetCO2 and less by subjective stress compared to controls. It was concluded that acquired sensitivity to physiological activity associated with habitual symptoms may account for excessive symptoms in patients with chronic health problems.

Exaggerated blood pressure (BP) response to exercise is a strong predictor of cardiovascular disease, although the mechanisms remain unknown. The purpose was to examine the association between systemic markers of vascular inflammation and exercise blood pressure (BP) responses. Participants were 191 healthy men and women (aged 45–59 years). Blood pressure was measured at baseline and during 8 min of steady state cycling ergometry exercise (at 50 W). Markers of vascular inflammation (fibrinogen, von Willebrand factor antigen, tumour necrosis factor-α, interleukin-6 [IL-6], C-reactive protein [CRP]) were measured at baseline together with other traditional risk factors including central adiposity, smoking, alcohol, and habitual physical activity. CRP (β = 0.30, p < 0.001), IL-6 (β = 0.25, p = 0.001), and fibrinogen (β = 0.14, p = 0.04) were associated with exercise systolic BP. The association with CRP remained significant after adjustment for age, sex, resting BP, and other risk factors. Other independent predictors of exercise BP included resting BP, female gender, waist–hip ratio, lower employment grade, and low physical activity level. In summary, central adiposity and vascular inflammatory processes may underlie exaggerated BP responses to acute exercise.

Objective
To examine whether ceiling effects at long inter beat intervals (IBIs)cause an underestimation of cardiac vagal control in regular exercisers by time and frequency-domain measures of respiratory sinus arrhythmia (RSA).
Methods
24-hour ECG and respiration recordings were performed in 26 regularly exercising subjects, actively engaged in aerobic training for the past year, and enrolled in supervised training in the six weeks pre-study, and in 26 age- and sex-matched non-exercisers. Sleep and waking levels of cardiac vagal control were estimated by RSA obtained through the peak–valley method, by the standard deviation of the IBIs, the root mean square of successive IBIs, and the high frequency IBI spectral power.
Results
In 11 of the exercisers the IBI–RSA relationship was characterized by a quadratic relationship. This reflected a ceiling effect at very long IBI values attained by regular exercisers, particularly during the nighttime recording. Irrespective of this ceiling effect, RSA as well as other heart rate variability (HRV) measures was still significantly larger in the exercisers with a quadratic IBI–RSA relationship than in non-exercisers or exercisers with a linear IBI–RSA relationship.
Conclusions
We conclude that a subgroup of regular exercisers is characterized by a low heart rate paired to high levels of cardiac vagal control. In these exercisers, vagal control is underestimated from HRV measures in ambulatory recordings. Inspection of the IBI–RSA relationship should be routinely added when HRV measures are used to index cardiac vagal control.

The prognostic power of heart rate recovery (HRR) after exercise has been well established but the exact origin of individual differences in HRR remains unclear. This study aims to estimate the heritability of HRR and vagal rebound after maximal exercise in adolescents. Furthermore, the role of voluntary regular exercise behavior (EB) in HRR and vagal rebound is tested.

Background
Antidepressant medication and running therapy are both effective treatments for patients with depressive and anxiety disorders. However, they may work through different pathophysiological mechanisms and could differ in their impact on physical health. This study examined effects of antidepressants versus running therapy on both mental and physical health.
Methods
According to a partially randomized patient preference design, 141 patients with depression and/or anxiety disorder were randomized or offered preferred 16-week treatment: antidepressant medication (escitalopram or sertraline) or group-based running therapy ≥2 per week. Baseline (T0) and post-treatment assessment at week 16 (T16) included mental (diagnosis status and symptom severity) and physical health indicators (metabolic and immune indicators, heart rate (variability), weight, lung function, hand grip strength, fitness).
Results
Of the 141 participants (mean age 38.2 years; 58.2 % female), 45 participants received antidepressant medication and 96 underwent running therapy. Intention-to-treat analyses showed that remission rates at T16 were comparable (antidepressants: 44.8 %; running: 43.3 %; p = .881). However, the groups differed significantly on various changes in physical health: weight (d = 0.57; p = .001), waist circumference (d = 0.44; p = .011), systolic (d = 0.45; p = .011) and diastolic (d = 0.53; p = .002) blood pressure, heart rate (d = 0.36; p = .033) and heart rate variability (d = 0.48; p = .006).
Limitations
A minority of the participants was willing to be randomized; the running therapy was larger due to greater preference for this intervention.
Conclusions
While the interventions had comparable effects on mental health, running therapy outperformed antidepressants on physical health, due to both larger improvements in the running therapy group as well as larger deterioration in the antidepressant group.
Trial registration
Trialregister.nl Number of identification: NTR3460.