Vertebral fracture during one repetition maximum testing in a breast cancer survivor: A case report.

RATIONALE: One repetition maximum (1-RM) testing is a standard strength assessment procedure in clinical exercise intervention trials. Because no adverse events (AEs) are published, expert panels usually consider it safe for patient populations. However, we here report a vertebral fracture during 1-RM testing. PATIENT CONCERNS: A 69-year-old breast cancer survivor (body-mass-index 31.6 kg/m2), 3 months after primary therapy, underwent 1-RM testing within an exercise intervention trial. At the leg press, she experienced pain accompanied by a soft crackling. DIAGNOSIS: Imaging revealed a partially unstable cover plate compression fracture of the fourth lumbar vertebra (L4) with a vertical fracture line to the base plate, an extended bone marrow edema and a relative stenosis of the spinal canal. INTERVENTIONS: It was treated with an orthosis and vitamin D supplementation. Another imaging to exclude bone metastases revealed previously unknown osteoporosis. OUTCOMES: The patient was symptom-free 6.5 weeks after the event but did not return to exercise. CONCLUSION: This case challenges safety of 1-RM testing in elderly clinical populations. LESSONS: Pre-exercise osteoporosis risk assessment might help reducing fracture risk. However, changing the standard procedure from 1-RM to multiple repetition maximum (x-RM) testing in studies with elderly or clinical populations would be the safest solution.

A low-dose, 6-week bovine colostrum supplementation maintains performance and attenuates inflammatory indices following a Loughborough Intermittent Shuttle Test in soccer players.

PURPOSE: The aim of the study was to investigate the effect of a 6-week, low-dose bovine colostrum (BC) supplementation on exercise-induced muscle damage (EIMD) and performance decline in soccer players following the Loughborough Intermittent Shuttle Test (LIST) during a competitive season period. METHODS: In a double-blind, randomized, placebo-controlled design, two groups of soccer players were allocated to a 3.2 g/day of whey protein (WP, N = 8) or BC (N = 10) and performed a pre- and a post-supplementation LIST. Maximum isometric voluntary contraction, squat jump (SQJ), countermovement jump, muscle soreness, blood cell counts, creatine kinase (CK), C-reactive protein (CRP) and interleukin-6 (IL-6) were monitored for 2, 24, 48, 72 h post-LIST. RESULTS: LIST induced transient increases in leukocytes, granulocytes, CK, muscle soreness, CRP, IL-6 and declines in lymphocytes and performance indices. Supplementation resulted in a faster recovery of SQJ, CK and CRP compared to pre-supplementation kinetics (trial × time: p = 0.001, 0.056, 0.014, respectively) and lower incremental area under the curve (iAUC) for IL-6, only in the BC group [pre-: 31.1 (6.78-46.9), post-: 14.0 (-0.16 to 23.5) pg h/ml, p = 0.034]. Direct comparison of the two groups after supplementation demonstrated higher iAUC of SQJ [WP: -195.2 (-229.0 to (-52.5)), BC: -15.8 (-93.2 to 16.8) cm h, p = 0.034], a trend for lower iAUC of CK in the BC group [WP: 18,785 (4651-41,357), BC: 8842 (4807-14,802) U h/L, p = 0.081] and a significant intervention × time interaction for CRP (p = 0.038) in favor of BC. CONCLUSIONS: Post-exercise EIMD may be reduced and performance better maintained by a low dose of BC administration following LIST in soccer players.

Larynx during exercise: the unexplored bottleneck of the airways.

Exercise-induced shortness of breath is not uncommon in otherwise healthy young people. Based on the presenting symptoms alone, it is challenging to distinguish exercise-induced asthma (EIA) from exercise-induced obstruction of central airways, sometimes leading to diagnostic errors and inadequate treatment. Central airway obstruction usually presents with exercise-induced inspiratory symptoms (EIIS) during ongoing exercise. EIIS tends to peak towards the end of an exercise session or immediately after its completion, contradicting symptoms of EIA typically peaking 3-15 min after the exercise has stopped. EIIS is usually associated with some form of laryngeal obstruction. Transnasal flexible laryngoscopy performed continuously throughout an incremental exercise test from rest to exhaustion or to intolerable symptoms is usually diagnostic, and also provides information that is important for further handling and treatment. Reflecting the complex anatomy and functional features of the larynx, exercise-induced laryngeal obstruction (EILO) appears to be a heterogeneous condition. Contradicting previous beliefs, recent literature suggests that laryngeal adduction in a majority of cases starts in supraglottic structures and that vocal cord adduction (VCD) most often occurs as a secondary phenomenon. However, EILO is poorly understood and more and better research is needed to unravel causal mechanisms. The evidence base for treatment of EILO is weak. Speech therapy, psychotherapy, biofeedback, muscle training, anticholinergic aerosols have all been applied, as has laser supraglottoplasty. Randomized controlled trials with well-defined and verifiable inclusion and success criteria are required to establish evidence-based treatment schemes.

Flecainide therapy suppresses exercise-induced ventricular arrhythmias in patients with CASQ2-associated catecholaminergic polymorphic ventricular tachycardia.

BACKGROUND: Calsequestrin-associated catecholaminergic polymorphic ventricular tachycardia (CPVT2) can cause sudden death in young individuals in response to stress. Beta-blockers are the mainstay medical treatment for patients with CPVT2. However, they do not prevent syncope and sudden death in all patients. Flecainide was reported to reduce exercise-induced ventricular arrhythmias (EIVA) in patients with ryanodine receptor-associated CPVT. The role of flecainide in CPVT2 is not known. OBJECTIVE: To summarize our experience in combining flecainide and beta-blockers in high-risk patients with CPVT2. METHODS: All patients with CPVT2 (10 patients) who have high-risk features (syncope, EIVA, or appropriate implantable cardioverter-defibrillator [ICD] shocks) despite beta-blockers with or without calcium channel blockers were treated with a combination of flecainide and beta-blockers. Exercise test was done before and after beginning treatment with flecainide. RESULTS: All patients had EIVA and 4 had appropriate ICD shocks before flecainide treatment. EIVA-included frequent ventricular premature beats and or ventricular tachycardia during the exercise test while on high dose of beta-blockers with or without calcium channel blockers before treatment with flecainide. After combination therapy with flecainide and beta-blockers, EIVA were suppressed completely in all patients. During follow-up of 15.5 ± 10.4 months (range 2-29 months), 8 patients were free of symptoms and free of arrhythmias. Two patients had 1 VT storm episode with recurrent ICD shocks despite repeated normal stress test. CONCLUSIONS: Flecainide can completely prevent ventricular arrhythmia during exercise and partially prevent recurrent ICD shocks in high-risk patients with CPVT2.

Tomato juice intake suppressed serum concentration of 8-oxodG after extensive physical activity.

BACKGROUND: DNA is constantly exposed to reactive oxygen species (ROS), spontaneously arising during the normal oxygen metabolism. ROS may result in temporary as well as permanent modifications in various cellular components such as lipids, proteins and DNA, which may have deleterious consequences. Demonstrating that a dietary supplementation of antioxidants can reduce oxidative DNA damage may provide evidence for the value of such supplementation in prevention of cancer and age related diseases. FINDINGS: The present study was conducted to address whether tomato juice protects against ROS induced by extensive physical exercise in untrained individuals. As a marker of oxidative stress, serum levels of 8-oxodG were monitored using a modified ELISA. An intervention was performed involving 15 untrained healthy subjects who performed a 20 min physical exercise at 80% of maximum pulse using an ergometer bicycle. Blood samples were taken before and one hour after the exercise. The procedure was repeated after 5 weeks with a daily intake of 150 ml tomato juice and followed by a 5 weeks wash-out period and another 5 weeks with a daily intake of tomato juice. The results indicated that a daily intake of tomato juice, equal to 15 mg lycopene per day, for 5 weeks significantly reduced the serum levels of 8-oxodG after an extensive physical exercise. CONCLUSION: These data strongly suggest that tomato juice has a potential antioxidant effect and may reduce the elevated level of ROS induced by oxidative stress.

Ascorbic acid supplementation attenuates exercise-induced bronchoconstriction in patients with asthma.

BACKGROUND: Previous research has shown that diet can modify the bronchoconstrictor response to exercise in asthmatic subjects. OBJECTIVE: Determine the effect of ascorbic acid supplementation on pulmonary function and several urinary markers of airway inflammation in asthmatic subjects with exercise-induced bronchoconstriction (EIB). METHODS: Eight asthmatic subjects with documented EIB participated in a randomized, placebo controlled double-blind crossover trial. Subjects entered the study on their usual diet and were placed on either 2 weeks of ascorbic acid supplementation (1500 mg/day) or placebo, followed by a 1-week washout period, before crossing over to the alternative diet. Pre- and post-exercise pulmonary function, asthma symptom scores, fraction of exhaled nitric oxide (FENO), and urinary leukotriene (LT) C4-E4 and 9alpha, 11beta-prostagladin (PG) F2] were assessed at the beginning of the trial (usual diet) and at the end of each treatment period. RESULTS: The ascorbic acid diet significantly reduced (p < 0.05) the maximum fall in post-exercise FEV1 (-6.4 +/- 2.4%) compared to usual (-14.3 +/- 1.6%) and placebo diet (-12.9 +/- 2.4%). Asthma symptoms scores significantly improved (p<0.05) on the ascorbic acid diet compared to the placebo and usual diet. Post-exercise FENO, LTC4-E4 and 9alpha, 11beta-PGF2 concentration was significantly lower (p<0.05) on the ascorbic acid diet compared to the placebo and usual diet. CONCLUSION: Ascorbic acid supplementation provides a protective effect against exercise-induced airway narrowing in asthmatic subjects.

Protective effect of fish oil supplementation on exercise-induced bronchoconstriction in asthma.

BACKGROUND: Previous research has demonstrated that fish oil supplementation has a protective effect on exercise-induced bronchoconstriction (EIB) in elite athletes, which may be attributed to its antiinflammatory properties. Since EIB in asthma involves proinflammatory mediator release, it is feasible that fish oil supplementation may reduce the severity of EIB in asthmatic subjects. STUDY OBJECTIVES: To determine the efficacy of fish oil supplementation on severity of EIB in subjects with asthma. DESIGN: Randomized, double-blind, crossover study. SETTING: Lung function and exercise testing in a university research laboratory. PATIENTS AND MEASUREMENTS: Sixteen asthmatic patients with documented EIB entered the study on their normal diet and then received either fish oil capsules containing 3.2 g of eicosapentaenoic acid and 2.0 g of docohexaenoic acid (fish oil diet, n = 8) or placebo capsules (placebo diet, n = 8) daily for 3 weeks. At the beginning of the study (normal diet) and at the end of each treatment phase, the following pre-exercise and postexercise measures were assessed: (1) pulmonary function; (2) induced sputum differential cell count percentage and proinflammatory eicosanoid metabolite (leukotriene C4 [LTC4]-leukotriene E4 [LTE4] and prostaglandin D2 [PGD2]) and cytokine (interleukin [IL]-1beta and tumor necrosis factor [TNF]-alpha) concentrations; and (3) eicosanoid metabolites leukotriene B4 (LTB4) and leukotriene B5 (LTB(5)) generation from activated polymorphonuclear leukocytes (PMNLs). RESULTS: On the normal and placebo diet, subjects exhibited EIB. However, the fish oil diet improved pulmonary function to below the diagnostic EIB threshold, with a concurrent reduction in bronchodilator use. Induced sputum differential cell count percentage and concentrations of LTC4-LTE4, PGD2, IL-1beta, and TNF-alpha were significantly reduced before and following exercise on the fish oil diet compared to the normal and placebo diets. There was a significant reduction in LTB4 and a significant increase in LTB5 generation from activated PMNLs on the fish oil diet compared to the normal and placebo diets. CONCLUSION: Our data suggest that fish oil supplementation may represent a potentially beneficial nonpharmacologic intervention for asthmatic subjects with EIB.

Exercise-induced second-degree atrioventricular block.

In this report we describe the case of a 56-year-old woman with normal 1:1 AV conduction at rest who developed 2:1 AV block during treadmill exercise testing. Electrophysiological study documented 2:1 AV block proximal to the His bundle with reappearance of 1:1 AV conduction at a higher pacing atrial rate. A gap phenomenon involving a proximal and distal part of the AV node may be a likely explanation of paradoxical AV conduction in our case.

Treadmill exercise in claudicants on aspirin results in improved antioxidant status but only minimal platelet activation.

The consequence of exercise on platelets remains controversial and adverse effects may result from repeated ischaemia reperfusion injury. We investigated platelet activation (platelet P-selectin (PS), and activated glycoprotein (Gp) IIb/IIIa), platelet-monocyte aggregates (PMA) and total plasma antioxidant status (TPAS) in claudicants after exercise. Twenty claudicants, taking 75 mg of aspirin daily, were subjected to repeated treadmill testing (3 km/h, 10% inclination). Blood was sampled before and after exercise. Activated GpIIb/IIIa, PS and PMA were quantified with flow cytometry. TPAS was quantified using a decolourisation assay. Percent positive cells for PS (pre-exercise 3.76% vs. 40 min post-exercise 4.10%; P < 0.05) and platelet-monocyte aggregates (pre-exercise: 25.31% vs. 40 min post-exercise 26.99%; P < 0.05) were significantly higher after exercise. Relative median fluorescence (RMF) for activated GpIIb/IIIa was significantly higher 40 min after exercise (pre-exercise: 3.04 vs. 40 min post-exercise: 4.01; P < 0.05). TPAS was significantly higher post-exercise (pre-exercise: 1.31 mmol/l vs. 1 min post-exercise: 1.40 mmol/l and 40 min post-exercise: 1.38 mmol/l; P < 0.01). Following moderate exercise, 'aspirin treated claudicants' show marginal platelet activation, PMA formation and a favourable improvement in antioxidant status. Further studies are required to assess the effect of additional antiplatelet agents and the significance of platelet-monocyte interactions. The possibility that aspirin contributes to the TPAS changes following exercise needs to be investigated.

Exercise test-induced arrhythmias.

Exercise testing commonly used by clinicians to characterize cardiovascular risk by detecting myocardial ischemia and assessing response to exercise. However, a consensus has not previously existed regarding the significance of exercise test-induced arrhythmias due to conflicting results from the available studies. Recent studies with longer follow-up and improved technology have therefore stimulated this current review of the topic. Despite the continued debate in the literature regarding the prognosis of ETIA in a general population, there is sufficient evidence to suggest that clinicians should closely evaluate and follow those patients with arrhythmias during exercise testing and aggressively modify risk factors for coronary artery disease.

MRI evaluation of topical heat and static stretching as therapeutic modalities for the treatment of eccentric exercise-induced muscle damage.

The aim of this study was to monitor the effects of topical heat and/or static stretch treatments on the recovery of muscle damage by eccentric exercise. For this purpose, 32 untrained male subjects performed intense eccentric knee extension exercise, followed by 2 weeks of treatment (heat, stretch, heat plus stretch) or no treatment (control, n=8/group). Isometric strength testing, pain ratings, and multi-echo magnetic resonance imaging of the thigh were performed before and at 2, 3, 4, 8, and 15 days following the exercise. Increased T2 relaxation time, muscle swelling, pain ratings, and strength loss confirmed significant muscle damage during the post-exercise period. Pain ratings and muscle volume recovered to baseline by 15 days, although muscle strength remained lower [77 (4) vs. 95 (3) kg pre-exercise, mean (SE)] and T2 values higher [32.2 (0.8) vs. 28.6 (0.2) ms pre-exercise]. Our results indicate that heat and/or static stretching does not consistently reduce soreness, swelling or muscle damage. The practical implication of our findings is that clinicians should be aware that prescribing heat and/or static stretching following intense eccentric or unaccustomed exercise will not enhance the recovery of damaged muscles.

Hyperventilation-precipitated cerebrovascular accident in a patient with sickle cell anaemia.

Hyperventilation exercise during electroencephalography precipitated a recurrence of right hemiplegia and aphasia in a patient with Hb SS disease. Although recovery of function started within hours of the event, full recovery has not occurred six months after. Hyperventilation provocative test during electroencephalography should be discouraged in patients with sickle cell anaemia.