PubMed Health⌕ Search

Biomedical subjects

T Swensen

Publications and source records attributed to T Swensen.

At least 19 recordsLinked to original sources
PubMed1998

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.

Adipose Tissue↗
PubMed1998

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.

Adaptation, Physiological↗
PubMed1997

[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.

Abscess↗
PubMed1994

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.

Adult↗
PubMed1993

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.

Adolescent↗
PubMed1983

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.

Diagnostic Errors↗
PubMed1983

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.

Gastrointestinal Diseases↗
PubMed1983

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.

Abdomen↗
PubMed1982

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.

Adolescent↗