Efficacy of Instability Resistance Training

The use of the stability ball as a platform for upper-body resistance training has gained much attention in recent years. However, the efficacy of such training regimens remains largely unstudied. The purpose of this study was to evaluate the influence of platform (unstable vs. stable, stability ball vs. flat bench) on strength and work capacity during barbell chest-press exercise. We also sought to determine the effects of a barbell chest-press training program performed on a stability ball or flat bench on strength, work capacity, and abdominal power. Fourteen young women (20 - 23 yr) performed a 1 repetition maximum (1RM) barbell chest-press and the YMCA bench press test (YBT) on a stability ball and flat bench, as well as two field tests measuring abdominal power. The women were then assigned to perform 3 weeks of barbell chest-press training on a stability ball (SB group) or flat bench (FB group); assignment was balanced based on 1RM strength. Barbell chest-press training included 3 sets of 3 - 5 repetitions at loads greater or equal to 85 % of 1RM. The 1RM barbell chest-press, YBT, front abdominal power test (FAPT), and side abdominal power test (SAPT) were used to evaluate changes in strength, work capacity, and abdominal power, respectively. The chest-press tests were completed on both platforms following the training program. Platform (stability ball vs. flat bench) had no influence on strength, but work capacity was initially 12 % lower on the stability ball compared to the flat bench. In response to training, both groups significantly increased strength and work capacity, and there were no group differences. The increase in 1RM strength was 15 % and 16 % on the stability ball and flat bench for the SB group, and 16 % and 19 % for the FB group, respectively. The increase in work capacity was 32 % and 13 % on the stability ball and flat bench for the SB group, and 27 % and 26 % for the FB group, respectively. Both groups significantly improved on the FAPT, and there were no group differences. Performance on the FAPT improved by 5 % for the SB group, and 22 % for the FB group. Performance on the SAPT did not change. Barbell chest-press training performed on either the stability ball or flat bench increased strength and work capacity, and these changes were transferable across platforms. Thus, the stability ball is an effective platform for barbell chest-press training in untrained women over a short duration.

The effects of massage on delayed onset muscle soreness

OBJECTIVES

The purpose of this study was to investigate the physiological and psychological effects of massage on delayed onset muscle soreness (DOMS).

METHODS

Eighteen volunteers were randomly assigned to either a massage or control group. DOMS was induced with six sets of eight maximal eccentric contractions of the right hamstring, which were followed 2 h later by 20 min of massage or sham massage (control). Peak torque and mood were assessed at 2, 6, 24, and 48 h postexercise. Range of motion (ROM) and intensity and unpleasantness of soreness were assessed at 6, 24, and 48 h postexercise. Neutrophil count was assessed at 6 and 24 h postexercise.

RESULTS

A two factor ANOVA (treatment v time) with repeated measures on the second factor showed no significant treatment differences for peak torque, ROM, neutrophils, unpleasantness of soreness, and mood (p > 0.05). The intensity of soreness, however, was significantly lower in the massage group relative to the control group at 48 h postexercise (p < 0.05).

CONCLUSIONS

Massage administered 2 h after exercise induced muscle injury did not improve hamstring function but did reduce the intensity of soreness 48 h after muscle insult.

Impact of resistance training on endurance performance. A new form of cross-training?

In accordance with the principles of training specificity, resistance and endurance training induce distinct muscular adaptations. Endurance training, for example, decreases the activity of the glycolytic enzymes, but increases intramuscular substrate stores, oxidative enzyme activities, and capillary, as well as mitochondrial, density. In contrast, resistance or strength training reduces mitochondrial density, while marginally impacting capillary density, metabolic enzyme activities and intramuscular substrate stores (except muscle glycogen). The training modalities do induce one common muscular adaptation: they transform type IIb myofibres into IIa myofibres. This transformation is coupled with opposite changes in fibre size (resistance training increases, and endurance training decreases, fibre size), and, in general, myofibre contractile properties. As a result of these distinct muscular adaptations, endurance training facilitates aerobic processes, whereas resistance training increases muscular strength and anaerobic power. Exercise performance data do not fit this paradigm, however, as they indicate that resistance training or the addition of resistance training to an ongoing endurance exercise regimen, including running or cycling, increases both short and long term endurance capacity in sedentary and trained individuals. Resistance training also appears to improve lactate threshold in untrained individuals during cycling. These improvements may be linked to the capacity of resistance training to alter myofibre size and contractile properties, adaptations that may increase muscular force production. In contrast to running and cycling, traditional dry land resistance training or combined swim and resistance training does not appear to enhance swimming performance in untrained individuals or competitive swimmers, despite substantially increasing upper body strength. Combined swim and swim-specific 'in-water' resistance training programmes, however, increase a competitive swimmer's velocity over distances up to 200 m. Traditional resistance training may be a valuable adjunct to the exercise programmes followed by endurance runners or cyclists, but not swimmers; these latter athletes need more specific forms of resistance training to realise performance improvement.

Derivation of prediction equations for RV in overweight men and women

PURPOSE

The purpose of this research was to derive and compare regression equations for predicting residual volume (RV) in overweight and normal weight adults.

METHODS

RV was determined on land, in 311 men and women, following an overnight fast, using the nitrogen-dilution technique. Subjects were then weighed underwater at RV; 5-10 underwater weights were recorded; and the heaviest 3 measurements were averaged as the underwater weight. Percent body fat was calculated using the Siri equation. Group analyses were performed on overweight men (N = 59, body fat > 25%) and women (N = 126, body fat > 30%) compared with normal weight men (N = 68, body fat < or = 25%) and women (N = 58, body fat < or = 30%). A stepwise regression was performed for each group using the Systat Statistical Package (Evanston, IL).

RESULTS

When RV was regressed on sex, age (yr), body weight (kg), and height (cm), sex was not found to be a significant predictor variable for RV. Subsequent regressions revealed that prediction equations for the overweight (RV = 0.0277 AGE + 0.0048 WT + 0.0138 HT - 2.3967, F = 44.0, P < 0.0000, SEE = 0.403) were different from those generated for normal weight men and women (RV = 0.0275 AGE + 0.0189 HT - 2.6139, F = 58.6, P < 0.0000, SEE = 0.405). Similar equations were obtained when a cross validation was performed on a separate sample of normal weight (N = 31) and overweight (N = 46) men and women.

CONCLUSION

These data suggest that prediction equations for RV are separate and distinct for the overweight and normal weight populations.

[Splenic abscess. Diagnosis and treatment]

A diagnosis of hospital discharges shows splenic abscess to be a rare condition, with one case per 10,000 discharges. Haematogenous seeding to the spleen from an infection at a distant site, most often endocarditis, has been the most common predisposing condition but an increase has been observed in immuno-suppressed patients too. Fever, leukocytosis and left upper quadrant pain are suggestive, but the signs and symptoms of splenic abscesses are often non-specific. Ultrasound and computed tomography are reliable diagnostic tools. Splenectomy and antibiotics have been the treatments of choice, with increasing use of percutaneous drainage as an alternative, in order to preserve splenic function. We describe a patient with a salmonella splenic abscess that was treated with percutaneous drainage and ciprofloxacin.

Adding polylactate to a glucose polymer solution does not improve endurance

Polylactate (PL), a semi-soluble amino acid/lactate salt, is a newly developed carbohydrate supplement purported to increase endurance. Our purpose was to determine if the addition of PL to a glucose polymer solution (GP) extends exercise time relative to a pure GP solution. In a double blind and random crossover design, 5 subjects exercised twice to exhaustion at 70% of VO2max. During the trials, they consumed GP or a GP/PL mixture at the rate of 0.3 g carbohydrate per kg of body wt in a 7% solution every 20 min until exhaustion. The GP/PL mixture contained 6.25 g GP to 0.75 g PL per 100 ml of water. Mixture composition was critical because PL, as supplied by the manufacturer and under our experimental conditions, produced severe gastro-intestinal efflux in concentrations > or = 2.5%; PL was tolerable in concentrations < or = 0.75%. At 20 min intervals, we measured VO2, respiratory exchange ratio, heart rate, and perceived exertion. At 30 min intervals, we measured serum glucose, insulin, free fatty acids, and glycerol as well as whole blood lactate and pH. We found that the addition of PL to a GP solution had no measurable physiological or performance effects.

The effect of moderate resistance weight training on peak arm aerobic power

The purpose of this study was to examine the effect of moderate resistance weight training (MRWT) on peak arm aerobic power as measured by arm cranking ergometry. Fourteen sedentary college age males, divided equally into two groups, served as subjects. The seven subjects in the MRWT group completed 12, 1-hr bouts of weight lifting over a 4 week period, exercising on Monday, Wednesday and Friday of each week. Exercise sessions included 3 sets of 10 repetitions of the following lifts: bench press, overhead dumbbell press, dumbbell arm curl, and behind the neck pull down. The remaining seven subjects served as a non-training control group, whose purpose was to account for possible learning effects on the arm ergometer test that could distort the statistical relevance of the aerobic power data. These subjects did not serve as a control for the weight training exercises, as the procedures used to determine muscular strength may produce a modest training effect. Peak arm aerobic power and muscular strength, as measured by the one-repetition maximum for each lift, were determined before and after the training program. The average increase in strength for all lifts combined for the trained group was 20.0%. They also experienced a 13.4% (p < .005) increase in peak arm aerobic power, whereas there was no significant change in this variable for the control group. It is concluded that peak arm aerobic power is enhanced by the changes in muscular strength produced by 4 wks of MRWT.

Abdominal ultrasonography in patients with uncharacteristic abdominal symptoms

Ultrasonography (US) was performed in a prospective study of 48 patients with uncharacteristic abdominal symptoms. All patients had been examined in other hospitals, but no diagnosis had been established. Pathologic US findings were encountered in five patients: fatty liver in two patients, gallstones in one patient, ovarian cyst in one, and liver metastases in another patient. US may be used as a diagnostic approach in patients with uncharacteristic abdominal complaints when conventional X-ray examinations are negative. In patients with psychosomatic disease a negative US result may be of importance in the psychiatric approach to these patients' disease.

Computer tomography of the abdomen in patients with uncharacteristic abdominal disturbances

Computer tomography (CT) was performed on 48 patients with uncharacteristic abdominal disturbances. Pathological CT findings were encountered in five patients, namely hepatic steatosis in three patients, liver metastases in one, and occlusion of the inferior vena cava in one. CT may be indicated in patients with uncharacteristic abdominal disorders when other investigations are negative. In some patients the negative result of the CT examination for organic disease was of great importance for the psychiatric approach to these patients' psychosomatic disease. In spite of this, the positive yield of abdominal CT seems to be highest when other less expensive examinations or tests have suggested abnormality of abdominal organs.

Reproducibility and observer variation at computed tomography and ultrasound of the normal pancreas

In order to evaluate the reproducibility of computed tomography (CT) and ultrasound (US), 13 patients with a normal pancreas were examined twice with the two techniques by the same observers. The results of the measurements of the pancreas were reproducible using both CT and US. In estimating the intraobserver variation at CT in 20 patients, the location and spread of the measurements of the diameters of the pancreatic head were reproducible, but the diameters of the pancreatic body and tail were significantly larger at the second observation. Further, the differences in the measurements of the size and dispersion of the pancreatic diameters at CT between two observers were significant, apart from the diameter of the pancreatic tail, where no significant difference was noted. The differences between two observers were greater than for the same. Using US, the results may indicate that the measurements were even less reproducible than using CT, both for the same observer and between two observers. However, all the measured diameters within the 95 per cent confidence intervals, were within the normal range. Consequently, even if most measurements differed significantly, these differences may probably not lead to any false conclusions concerning the limits of the normal size of the pancreas.

Computed tomography and ultrasound of the normal pancreas

Computed tomography (CT) and ultrasound (US) were performed on 47 patients with a normal pancreas. CT was a significantly better method than US to demonstrate the pancreatic body and tail. The pancreatic head was also shown more often using CT than US, but this difference was not statistically significant. The diameters of the different parts of the pancreas measured at CT were significantly larger than measured at US. The explanation is most probably that the widths of the splenic and superior mesenteric veins are added to the diameters of the pancreas measured at CT, while using US, these vessels are clearly differentiated from the pancreatic tissue. US was a significantly better technique than CT to register the vascular structures surrounding the pancreas, except from the left renal vein, which was more often demonstrated at CT.

Endoscopic retrograde cholangio-pancreatography in primary and secondary tumours of the pancreas

Twelve of 69 histologically proven pancreatic malignancies were secondary tumours. The most common pattern in the pancreatogram was occlusion and stenosis of the main pancreatic duct. It was not possible radiologically to differentiate between primary and secondary lesions.

Barium enema in pediatric intussusception; a review of 108 cases

A material of 108 patients with 125 intussusceptions was evaluated retrospectively. Barium enema is recommended as an excellent diagnostic tool. Reduction should be tried in all cases except those with signs of peritonitis, because the enema causes fewer complications and leads to a considerably decreased hospital stay.

Endoscopic retrograde brush cytology in patients with primary and secondary malignancies of the pancreas

Endoscopic retrograde brush cytology (ERBC) was performed in 29 patients with primary pancreatic malignancies verified later by histology. Results were positive in 21 patients, suspicious in five, and negative in three. ERBC performed in seven patients with uncertain findings at endoscopic retrograde cholangiopancreatography (ERCP) was positive for malignancy in six and suspicious in one. Endoscopic aspiration cytology (EAC) performed in 10 patients with primary tumours was positive for malignancy in three, suspicious in two, and negative in five cases. ERBC and/or EAC performed in five cases with secondary tumours were positive for malignancy in one and negative in four. It is concluded that ERBC gives a high rate of positive or suspicious (90%) diagnosis of malignancy in patients with primary pancreatic lesions. In secondary tumours cytology seems to be negative in most cases. The study further shows that many of the malignant tumours found by ERP are secondary lesions. Cytology is often able to detect malignancy when ERP has proved inconclusive.

Juxtapapillary duodenal diverticula and abnormalities by endoscopic retrograde cholangio-pancreatography (ERCP)

In a consecutive series of 174 patients the biliary and pancreatic ducts were demonstrated by endoscopic retrograde cholangio-pancreatography (ERCP). In 84 patients with normal duct systems, juxtapapillary diverticula were found in 5 patients (6%). In 90 cases with ductal abnormalities due to biliary concrements, dilated common bile duct and pancreatitis, diverticula were found in 35 patients (39%). In patients with abnormalities in both duct systems, diverticula were found in 52%, and in patients with changes in one duct system diverticula were found in 33%. The difference in occurrence of diverticula in patients with normal duct systems and pathological duct systems was statistically significant (p less than 0.02). The findings indicate a correlation between juxtapapillary diverticula and pathological changes due to biliary concrements, dilated common bile duct without concrements and pancreatitis.