Exercise training produces a vast array of physiological adaptations, ranging from changes in metabolism to muscle mitochondrial biogenesis. Researchers studying the physiological effects of exercise often use animal models that employ forced exercise regimens that include aversive motivation, which could activate the stress response. This study examined the effect of forced treadmill running (8 wk) on several physiological systems that are sensitive to training and stress. Forced treadmill running produced both positive and negative physiological adaptations. Indicative of positive training adaptations, exercised male Sprague-Dawley rats had a decrease in body weight gain and an increase in muscle citrate synthase activity compared with sedentary controls. In contrast, treadmill running also resulted in the potentially negative adaptations of adrenal hypertrophy, thymic involution, decreased serum corticosteroid binding globulin, elevated lymphocyte nitrite concentrations, suppressed lymphocyte proliferation, and suppressed antigen-specific IgM. Such alterations in neuroendocrine tissues and immune responses are commonly associated with chronic stress. Thus treadmill running produces both positive training adaptations and potentially negative adaptations that are indicative of chronic stress. Researchers employing forced activity need to be aware that this type of exercise procedure also produces physiological adaptations indicative of chronic stress and that these changes could potentially impact other measures of interest.

Objective Myofascial trigger points (MTrPs) are focal disruptions in skeletal muscle that can refer pain to the head and reproduce the pain patterns of tension-type headache (TTH). The present study applied massage focused on MTrPs of subjects with TTH in a placebo-controlled, clinical trial to assess efficacy on reducing headache pain. Methods Fifty-six subjects with TTH were randomized to receive 12 massage or placebo (detuned ultrasound) sessions over six weeks, or to wait-list. Trigger point release (TPR) massage focused on MTrPs in cervical musculature. Headache pain (frequency, intensity and duration) was recorded in a daily headache diary. Additional outcome measures included self-report of perceived clinical change in headache pain and pressure-pain threshold (PPT) at MTrPs in the upper trapezius and sub-occipital muscles. Results From diary recordings, group differences across time were detected in headache frequency (p=0.026), but not for intensity or duration. Post hoc analysis indicated headache frequency decreased from baseline for both massage (p<0.0003) and placebo (p=0.013), but no difference was detected between massage and placebo. Subject report of perceived clinical change was a greater reduction in headache pain for massage than placebo or wait-list groups (p=0.002). PPT improved in all muscles tested for massage only (all p's<0.002). Discussion Two findings from this study are apparent: 1) MTrPs are important components in the treatment of TTH, and 2) TTH, like other chronic conditions, is responsive to placebo. Clinical trials on headache that do not include a placebo group are at risk for overestimating the specific contribution from the active intervention.

High-intensity treadmill exercise increases the expression of a cardioprotective, inducible 72-kDa stress protein (SP72) in cardiac muscle. This investigation examined whether voluntary free wheel exercise training would be sufficient to confer a similar response. Male Sprague-Dawley rats were randomly assigned to either treadmill (TM-Tr) or free wheel (FW-Tr) training groups. By the end of the 8-wk training period, TM-Tr animals ran 1 h/day, 5 days/wk up a 10% grade, covering a distance of 8,282 m/wk. FW-Tr rats ran, on average, 5,300 m/wk, with one-third of the animals covering distances similar to those for the TM-Tr group. At the time of death, hearts of trained and caged sedentary control (Sed) animals were divided into left (LV) and right (RV) ventricles. Citrate synthase activity and the relative immunoblot contents of SP72, SP73 (the constitutive isoform of the SP70 family), and a 75-kDa mitochondrial chaperone (SP75) were subsequently determined. LV and RV did not differ on any measure, and SP73, SP75, and citrate synthase were not affected by training. Cardiac SP72 levels were elevated over fourfold in both ventricles of TM-Tr compared with RV of FW-Sed rats. Despite the animals having run a similar total distance, cardiac SP72 content in FW-Tr rats was not different from that in Sed animals. These data indicate that voluntary exercise training is insufficient to elicit an elevation of SP72 in rat heart and suggest that exercise intensity may be a critical factor in evoking the cardioprotective SP72 response.

The current study addressed whether physical activity can buffer stress-induced "behavioral depression" and immunosuppression. Adult, male Sprague-Dawley rats were housed with either a mobile (physically active) or immobile (sedentary) running wheel and exposed to either stress (inescapable tail shock) or no stress (home cage control). Voluntary wheel running began 4 wk before stressor exposure. Immediately before stress, all rats were administered an intraperitoneal injection of keyhole limpet hemocyanin (KLH; 200 microg), and anti-KLH Ig was measured weekly for 4 wk using ELISA. Prior physical activity reduced the stress-induced behavioral depression and prevented the stress-induced suppression of anti-KLH IgM and IgG(2a) antibodies. Anti-KLH IgG(1) was stress insensitive. These data suggest that physical activity can buffer the negative impact of stress on behavior and acquired immune function.

Use of massage therapy by the general public has increased substantially in recent years. In light of the popularity of massage therapy for stress reduction, a comprehensive review of the peer-reviewed literature is important to summarize the effectiveness of this modality on stress-reactive physiological measures. On-line databases were searched for articles relevant to both massage therapy and stress. Articles were included in this review if (i) the massage therapy account consisted of manipulation of soft tissues and was conducted by a trained therapist, and (ii) a dependent measure to evaluate physiological stress was reported. Hormonal and physical parameters are reviewed. A total of 25 studies met all inclusion criteria. A majority of studies employed a 20–30 min massage administered twice-weekly over 5 weeks with evaluations conducted pre-post an individual session (single treatment) or following a series of sessions (multiple treatments). Single treatment reductions in salivary cortisol and heart rate were consistently noted. A sustained reduction for these measures was not supported in the literature, although the single-treatment effect was repeatable within a study. To date, the research data is insufficient to make definitive statements regarding the multiple treatment effect of massage therapy on urinary cortisol or catecholamines, but some evidence for a positive effect on diastolic blood pressure has been documented. While significant improvement has been demonstrated following massage therapy, the general research body on this topic lacks the necessary scientific rigor to provide a definitive understanding of the effect massage therapy has on many physiological variables associated with stress.