Effects of high-intensity resistance training and low-intensity resistance training with vascular restriction on bone markers in older men

The aim of this study was to examine and compare the effects of different resistance training protocols on bone marker concentrations in older men. Thirty-seven healthy older male subjects were assigned to one of three groups: high-intensity resistance training (HI-RT, age?=?57.5?±?0.8); low-intensity resistance training with vascular restriction (LI-VRT, age?=?59.9?±?1.0); and control (CON, age?=?57.0?±?1.1). Blood samples were collected before and after 6?weeks of resistance training to measure the changes in bone formation [bone alkaline phosphatase, (Bone ALP)] and resorption (C-terminal cross-linking telopeptide of Type-I collagen, CTX) marker concentrations. A significant main effect for time was detected in Bone ALP to CTX ratio for the exercise groups (p??LI-VRT, p?相似文献   

Effect of different types of resistance exercise on arterial compliance and calf blood flow

Low-intensity blood flow restricted (LI-BFR) resistance training has been shown to produce comparable increases in muscle hypertrophy to traditional high-intensity (HI) resistance training. However, a comparison of the acute vascular responses between the two types of exercise has not been made. The purpose of this study is to compare the acute vascular responses of HI, low-intensity (LI), and LI-BFR resistance exercise. Using a randomized, cross-over design, 11 young (28 ± 5 years) males completed three acute resistance exercise bouts (HI, LI and LI-BFR). Before (Pre), and starting at 15- and 45-min after each exercise bout, large (LAEI) and small (SAEI) artery compliance and calf blood flow were assessed. Calf blood flow was normalized per unit pressure as calf vascular conductance (CVC). Repeated measures (condition × time) ANOVA revealed a main time effect for LAEI and a main condition effect for SAEI. LAEI increased following exercise but returned to baseline at 45-min post. SAEI was greater during the HI condition compared to the LI or LI-BFR conditions. There was a significant condition × time interaction for CVC. CVC was elevated at 15- and 45-min post during the HI condition and at 15-min following the LI condition. CVC was not altered following the LI-BFR condition. These results suggest that HI, LI, and LI-BFR resistance exercise cause similar acute increases in large artery compliance but HI causes greater increases in small artery compliance and calf vascular conductance than LI or LI-BFR resistance exercise.     

Relationships Between Body Composition, Muscular Strength, and Bone Mineral Density in Estrogen-Deficient Postmenopausal Women

The purpose of this study was to examine relationships between muscular strength, body composition, and bone mineral density (BMD) in untrained postmenopausal women who are not on hormone replacement therapy (HRT). Fifty-five women (age: 63.3 ± 0.6 yr) completed menstrual history, physical activity, and calcium intake questionnaires. Total and regional body composition and total body, anteroposterior lumbar spine, nondominant forearm, and right proximal femur BMD were measured using dual-energy X-ray absorptiometry (DXA) (GE Lunar Prodigy, Prodigy enCORE software version 10.50.086, Madison, WI). Participants performed strength tests for 3 upper body and 5 lower body resistance exercises. Women with a relative skeletal muscle mass index (RSMI) value less than 5.45 kg/m² were defined as a sarcopenia group (SAR). SAR had significantly (p < 0.05) lower total body and forearm BMD compared with those who were not sarcopenic. BMD sites were significantly correlated with upper body strength (UBS) and lower body strength (LBS) (r = 0.28–0.50, p < 0.01), with the strength of relationship being site specific. Strength and fat mass (FM) significantly predicted total body BMD (R² = 0.232–0.241, p < 0.05), FM variables predicted spine BMD (R² = 0.109–0.140, p < 0.05), and LBS and RSMI predicted hip BMD sites (R² = 0.073–0.237, p < 0.05). Body composition variables failed to significantly predict LBS. In conclusion, the contribution of body composition and strength variables to BMD varied by site as FM was more important for total body, forearm and spine BMD, and LBS exerted greater influence on the hip sites.     

The effect of acute blood-flow-restricted resistance exercise on postexercise blood pressure

Introduction: Blood‐flow‐restricted (BFR) exercise is an emerging type of exercise that may be particularly beneficial to elderly or special populations. These populations may also benefit from reductions in blood pressure (BP). The effect of BFR exercise on postexercise BP has not been examined; this should first be examined in a young, healthy population as a preliminary investigation. Purpose: The main purpose of this study was to determine whether postexercise hypotension (PEH) occurred following low‐intensity [20% 1 repetition maximum (1‐RM)] BFR resistance exercise. A secondary purpose was to compare this response to both a work‐matched low‐intensity (20% 1‐RM) (LI) and a traditional high‐intensity (70% 1‐RM) resistance exercise bout (HI). Methods: In a randomized cross‐over design, ten normotensive, young (18–35 years) men performed one of the three lower‐body resistance exercise bouts (HI, LI or low‐intensity BFR) during separate visits to the laboratory. Brachial BP, cardiac ultrasound and calf blood flow measurements were taken prior to and 30 and 60 min following exercise. Repeated measures analysis of variance (3 × 3; condition × time) was performed on all variables. Results: A significant interaction (P<0·05) was found for brachial systolic blood pressure which decreased following HI only. Significant interactions (P<0·05) were also seen for heart rate, total peripheral resistance and calf vascular resistance. Conclusion: Postexercise hypotension occurred only following HI. Thus, if one is exercising with the intent of lowering BP, HI resistance exercise may be more useful than low‐intensity BFR resistance exercise.     

25The effect of lipase supplementation on upper gastrointestinal symptoms and gastric myoelectrical activity induced by a high fat meal in healthy volunteers.

Background/Aims: Dyspepsia symptoms of abdominal discomfort, fullness, early satiety, and nausea occur after ingestion of meals in 20–30% of the population. Gastric dysrhythmias are exhibited by approximately 55% of dyspepsia patients. Currently there are limited therapies to reduce these symptoms. Gastric and pancreatic lipases are key enzymes in fat digestion, and hydrolyze fat into fatty acids and monoglycerides. The aims of this study were to characterize the effects of a high fat meal on upper gastrointestinal symptoms and gastric myoelectrical activity, and to evaluate the effect of acid‐resistant lipase supplementation on the same outcomes. Methods: Sixteen healthy volunteers enrolled in a double‐blind, placebo controlled, cross‐over trial were given a high fat meal (Pulmocare^®) that was 55% fat, 28% carbohydrates, and 17% protein (237 ml; 355 Kcal). A capsule containing 280 mg of acid‐resistant lipase (Amano Enzyme USA) or placebo was administered immediately before ingestion of the meal. The order of conditions was counterbalanced, and visits were separated by at least one week. At each visit, individuals completed a Visual Analog Scale (VAS) concerning symptoms of nausea, stomach fullness, hunger, bloating, and abdominal discomfort at baseline, immediately after the meal, and at 10, 20, 30, 45, and 60 minutes after the meal. Electrogastrograms (EGGs) were recorded throughout each visit to assess gastric myoelectrical activity. Results: Nausea, bloating, and stomach fullness were significantly increased 10 min after ingestion of the meal (ps < 0.05), and hunger was significantly decreased (p < 0.001); there was also a significant decrease in normal gastric myoelectrical activity (3 cycles min^?1), and a significant increase in tachygastria (3.7–10 cycles min^?1) at 10 min after the meal (ps < 0.05). By 45 min after the meal, dyspepsia symptoms and tachygastria had decreased significantly from immediately after the meal, and normal gastric myoelectrical activity had increased significantly (ps < 0.05). Stomach fullness was significantly lower with lipase supplementation than with placebo condition at 20 and 30 min after the meal (p < 0.05); no effect of lipase supplementation on gastric myoelectrical activity was detected. Conclusions: (1) The high fat meal induced dyspepsia symptoms and gastric dysrhythmias, suggesting the meal may be a useful test for assessing gastric neuromuscular disorders; and (2) Acid‐resistant lipase supplementation decreased stomach fullness after ingestion of the meal, and warrants further study in individuals with functional dyspepsia.     

The midaortic syndrome: diagnosis and treatment

The midaortic syndrome is an unusual entity seen in children and adolescents. It is characterized by severe narrowing of the abdominal aorta with progressive involvement of the renal and visceral branches. Eleven patients (aged 5 months to 15 years) suspected of having midaortic syndrome were examined preoperatively and postoperatively. All patients had hypertension and were examined with midstream aortography. All aortograms showed a smooth, segmental stenosis of the abdominal aorta and severe bilateral proximal renal artery stenosis. In three patients, percutaneous transluminal angioplasty of the renal artery was attempted, two preoperatively and one for a postoperative stricture. None showed long-term success, presumably due to the progressive nature of the disease. Grafts were surgically placed in ten patients and produced successful results in nine.     

Splenic Syndrome due to Sickle Cell Trait amongst Indian Soldiers Serving in Kashmir

Background

Heterozygous transmission of gene for Haemoglobin S leads to sickle cell trait. Mostly the trait remains silent with no additional morbidity or mortality. When these persons migrate to higher altitudes, in times of high oxygen demand, some of them develop splenic infarction. This is a rare phenomenon and only 47 such cases had been reported till 2005.

Methods

This study was conducted at an Indian military hospital serving the troops deployed in Kashmir valley at altitudes ranging from 5500 ft to 13000 ft. When two consecutive splenectomies for splenic abscesses, turned out to be sickling induced infarction histopathologically, we reviewed splenectomy specimens received in last six years for evidence of sickling.

Result

Out of 33 splenectomies performed during the period of study, 22 were due to trauma (gun shot injury 11; splinter injury one and blunt injury 10). Of the rest eleven, who presented without any history of trauma, seven had evidence of vascular occlusion with aggregates of sickled red blood cells. In none, Gram stain or Periodic Acid Schiff stain revealed any bacterial or fungal colonies. One patient of splenic syndrome was found to have unrecognised sickle cell trait and he was managed conservatively.

Conclusion

Sickle cell trait should be excluded before considering splenectomy in ethnically vulnerable patients presenting with splenic syndrome. An uncomplicated splenic infarction can be managed conservatively.Key Words: Sickle cell trait, Splenic infarction, Splenic syndrome