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Biomedical subjects

F Ingjer

Publications and source records attributed to F Ingjer.

28 records · Page 2Linked to original sources
PubMed1979

Correlation of individual skeletal muscle fibres from "semithin" sections stained with p-phenylene-diamine and histochemical sections incubated for myofibrillar ATP-ase.

Muscle fibres in transverse "semithin" sections of osmium-fixed and plastic embedded muscle tissue stained with p-phenylene-diamine has been classified into three types (M, INT and H) and correlated to the same fibres in neighboring sequential preincubated myofibrillar ATP-ase sections. A close correlation, but no equality was found between the fibre types classified according to the ATP-ase and the p-phenylene-diamine methods. On the average, the content of mitochondria and fat droplets was highest in the ATP-ase classified type I fibres (dominated by M fibres), and higher in the endurance trained than in the untrained subjects.

Adenosine Triphosphatases↗
PubMed1979

Capillary supply and mitochondrial content of different skeletal muscle fiber types in untrained and endurance-trained men. A histochemical and ultrastructural study.

The number of capillaries per fiber, per mm2, around each fiber type and relative to fiber area was determined in six untrained subjects (UT) and six elite cross-country skiers (ET). Average values for maximal oxygen uptake were 49.8 ml . kg-1 . min-1 (UT) and 77.9 ml . kg-1 . min-1 (ET). Type I fibers constituted 39.2% (UT) and 68.6% (ET), type II A fibers 39.6% (UT) and 19.2% (ET), while 12.8% (UT) and 6.6% (ET) of the fibers were type II B. The mean fiber area for the type II A fibers was significantly greater (p less than 0.01) than the areas for type I and II B in the untrained group. The average numbers of capillaries around each fiber type (CA) were 4.76-4.84-2.94 (UT) and 7.79-6.63-4.5 (ET) for type I, II A, and II B, respectively. There was a significant difference (p less than 0.01) in the CA values relative to fiber area for all fiber types in both groups, being highest for type I and lowest for type II B. The CA increased linearly with increasing size of the fibers for all fiber types in both groups. The mitochondrial content was determined semiquantitatively for each fiber type. The differences in capillary supply between the fiber types are accompanied by similar differences in mitochondrial content. The results indicate that endurance training increases the capillary supply of all fiber types in the human quadriceps muscle. The fact that light microscopical studies have given lower capillarization values than those obtained with the electron microscope is discussed.

Adult↗
PubMed1979

Effects of endurance training on muscle fibre ATP-ase activity, capillary supply and mitochondrial content in man.

Seven young females were subjected to 24 weeks of intensive endurance training. Adaptive changes in myofibrillary ATP-ase activity, capillary supply and mitochondrial content were investigated with light- and electron microscopy in needle biopsies from the quadriceps femoris. 1. The average value for the maximal oxygen uptake increased from 45.7 to 57.2 (ml . kg-1 min-1) (25.2%, P less than 0.005). 2. The average number of capillaries per muscle fibre increased from 1.39 to 1.79 (28.8%, P less than 0.005). Since no significant change in fibre area was found, this suggests that a considerable number of new capillaries have been formed during the training period. 3. An increased capillary supply of all fibre types was found, being greatest for type I and smallest for type IIB. 4. The relative amount of type I fibres before and after the training period was 57.9 and 56.5% respectively (n.s.), for type IIA fibres 26.4 and 31.5% (P less than 0.005), for type IIB fibres 9.2 and 3.4% (P less than 0.005) and for type IIC fibres 0.4 and 2.2% (P less than 0.005). Thus, in the type II group, significant changes in subtypes take place during the endurance training. The data suggest that type IIAB may represent a transitional state between type IIA and IIB. 5. Correlation of capillary supply, myofibrillar ATP-ase activity and mitochondrial content (determined semiquantitatively of individual muscle fibres indicators that the capillary supply to a given fibre is more closely related to its mitochondrial content than to the fibre type as determined on the basis of myofibrillar ATP-ase activity.

Adenosine Triphosphatases↗
PubMed1978

Capillary supply of skeletal muscle fibers in untrained and endurance-trained women.

Muscle fiber diameters and number of capillaries per fiber, per mm2 and around each fiber were determined in needle biopsies from the lateral part of the quadriceps muscles of 11 young women. Six subjects were untrained (UT) and five were endurance-trained athletes (ET). Average values for maximal oxygen uptake were 43.9 (UT) and 62.1 ml/kg X min (ET). Mean fiber diameter was somewhat smaller in the UT than in the ET group (39.1 and 42.7 micrometer), but the difference was not statistically significant. Fibers with the highest content of mitochondria were on the average 9 micrometer thicker than those with the lowest content. The capillary per fiber ratios were 1.11 +/- 0.07 (mean +/- S.E.) and 1.69 +/- 0.13 in the UT and ET groups, respectively. The number of capillaries around each fiber was 3.04 +/- 0.17 (UT) and 4.42 +/- 0.31 (ET). After correction for shrinkage the number of capillaries per mm2 was 301 (UT) and 404 (ET). The capillary per fiber ratio increased with increasing fiber diameter and with the content content of mitochondria.

Adult↗
PubMed1978

Comparison of diving bradycardia and maximal aerobic power.

It has previously been suggested that diving bradycardia might be more pronounced in physically trained subjects than in unconditioned ones. Therefore, the cardiac responses to apneic face immersion in water of 25 +/- 1 degree C during rest and exercise in 24 males and females, ranging in age from 21-37 years, were compared to the subjects' levels of physical fitness, as estimated by maximal aerobic power. These values ranged from 46-74 ml.kg-1.min-1. The diving bradycardia was greatly intensified when the face immersion was superimposed on a state of apneic exercise. However, a correlation of the individuals' maximal aerobic power and the mean degree of bradycardia displayed during various maneuvers of apneic face immersion did not approach statistical significance. It is concluded that there exists no relationship between bradycardia and physical fitness, as judged from maximal aerobic power.

Adult↗
PubMed1977

Capillary supply of skeletal muscle fibers in untrained and endurance-trained men.

Muscle fiber diameters and numbers of capillaries per fiber, per square millimeter, and around each fiber were determined in needle biopsies from the lateral part of the quadriceps muscle of 23 young men. Twelve subjects were untrained (UT) and eleven were endurance-trained (ET) athletes. Average values for maximal oxygen uptake were 51.3 (UT) and 72.0 ml/kg-min (ET). Mean fiber diameters were not significantly different in the two groups (48.8 and 49.1 micron). The capillaries per fiber ratios were 1.77+/-0.10 and 2.49+/-0.08 (mean+/-SE) in the UT and ET groups, respectively. The numbers of capillaries around each fiber were 4.43+/-0.19 (UT) and 5.87+/-0.18 (ET). The numbers of capillaries per mm2 were 585+/-40 (UT) and 821+/-28 (ET). Fiber diameters were 28% smaller in ultrathin than in fresh-frozen sections from the same biopsies. After correction for this difference, the numbers of capillaries per mm2 were 305 and 425 in the UT and ET, respectively. The capillaries per fiber ratio increased with increasing fiber diameter, but not sufficiently to maintain the number of capillaries per mm2. Fibers containing many mitochondria are surrounded by more capillaries than fibers with few mitochondria.

Adolescent↗
PubMed1977

Assessment of maximal aerobic power in specifically trained athletes.

Maximal aerobic power of 37 athletes (14 females and ten male cross-country skiers, eight male rowers and five male cyclists) was determined during uphill running on the treadmill and during maximal performance of their specific sport activity. For the skiers a significantly (P less than 0.005) higher VO2max was found during uphill skiing than during running, the differences being 2.9 and 3.1% for the females and males, respectively. The rowers and cyclists obtained a difference of 4.2 and 5.6%, respectively (P less than 0.01). The largest individual differences between the two test procedures were 12.2, 5.4, 14.3, and 7.9% for female and male cross-country skiers, rowers, and cyclists, respectively. It is concluded that in evaluation of maximal aerobic power of atheletes, it becomes important to select a work situation which allows optimal use of the specifically trained muscle fibres. This means that the test preferably should be identical with the subjects' specific sport activity, under the assumption that a reasonably large muscle mass is engaged during the performance.

Female↗