Comparison of resistance training using barbell half squats and trap bar deadlifts on maximal strength, power performance, and lean mass in recreationally active females: an eight-week randomised trial.

BACKGROUND: The aim of this study was to investigate the effect of high load resistance training using barbell half squats compared with trap bar deadlifts on maximal strength, power performance, and lean mass in recreationally active females. METHODS: Twenty-two recreationally active female participants (age: 26.9 ± 7.7 yrs.; height: 166.0 ± 5.1 cm; weight: 68.6 ± 9.9 kg) were randomly assigned to either a barbell half squat group (SG: n = 10) or trap bar deadlift group (DG: n = 12). Training consisted of twice-weekly sessions for eight weeks. Both groups completed one-repetition maximum (1RM) testing for both barbell half squat and trap bar deadlift groups. Countermovement jump (CMJ) and sprint performance were also assessed. Total body (TBLM) and leg lean mass (LLM) were measured with dual-energy x-ray absorptiometry. Between-group differences were analysed using analysis of covariance. RESULTS: SG tended to improve 1RM half squat (21.0 ± 11.5 kg vs. 13.1 ± 7.5 kg) more than DG (mean difference (MD): 8.0 kg, 95% CI: -0.36 - 16.3 kg). A similar pattern in favour of DG (18.4 ± 11.2 vs. 11.7 ± 8.1 kg) compared to SG was observed (MD: 6.5 kg, 95% CI: -2.5 - 15.6 kg). No between-group differences for sprint, jump or lean body mass changes was observed. For groups combined, the following changes in CMJ (2.0 ± 2.4 cm), 5-m sprint (-0.020 ± 0.039 s), 15-m sprint (-0.055 ± 0.230 s), TBLM (0.84 ± 1.12 kg), and LLM (0.27 ± 0.59 kg) was observed. CONCLUSIONS: An exercise intervention consisting of half squats or trap bar deadlift were associated with improved muscle strength, power, and lean mass. Our findings suggests that in recreationally active females, exercise selection is less of a concern provided that heavy loads are applied, and relevant muscle groups are targeted.

Calpain inhibitor A-558693 in experimental focal cerebral ischemia in rats.

OBJECTIVES: Calpains are intracellular proteases, which are activated in various cerebral injuries. We studied the expression of mu-calpain in a model of focal cerebral ischemia/reperfusion and the efficacy of the calpain inhibitor A-558693. METHODS: A transient occlusion of the middle cerebral artery was produced in male Wistar rats by using the suture model with 3 hours of ischemia and 24 hours of reperfusion. Six animals were given the calpain inhibitor and six animals were treated with placebo. The infarct size was determined by the loss of the calpain substrate microtubule-associated protein-2 (MAP-2) immunohistochemistry using volumetry in serial slices of the brains. Furthermore mu-calpain positive-stained cells were detected by immunohistochemistry and western blotting. RESULTS: In placebo-treated animals the mu-calpain expression was significantly increased in the ischemic hemisphere compared with the contralateral non-ischemic hemisphere (88.6 versus 10.5% in the basal ganglia, 60.7 versus 10.7% in the cortex, p < 0.001, respectively) with a subsequent loss its substrate MAP-2. However, the use of the calpain inhibitor A-558693 did not significantly change the mu-calpain expression, nor significantly reduce the infarct volume. DISCUSSION: The present data indicate that mu-calpain proteolysis plays an important role in the chain of events following cerebral ischemia. However, the calpain inhibitor A-558693 failed to prevent these changes.

Tissue-saving infarct volumetry using histochemistry validated by MRI in rat focal ischemia.

Lesion size is an important outcome parameter in experimental stroke research. However, most methods of measuring the infarct volume in rodents either require expensive equipment or render the brain tissue unusable for further analysis. We report on an inexpensive, tissue-saving method for quantifying the infarct volume in small rodents. After 3 h of middle cerebral artery occlusion (MCAO) and 24 h of reperfusion in male Wistar rats, the lesion was first identified using MRI with T2-weighted sequences. The infarct was then visualized in unfixed brain cryosections using microtubule associated protein 2 (MAP2)-immunohistochemistry and silver infarct staining. The lesion areas detected by all three different methods completely overlapped. The infarct volume was calculated for each method from the lesion area size on serial sections and the distance between them. Significant differences in lesion size were found between the individual animals (p = 0.000056), but not between different methods (p > 0.05). MAP2 immunohistochemistry is a convenient and valid method to measure stroke lesion volume; in addition 98% of the brain tissue is saved and available for use in further histological, immunohistochemical, and biochemical analysis.