University of Jyväskylä

About: University of Jyväskylä is a education organization based out in Jyvaskyla, Finland. It is known for research contribution in the topics: Population & Context (language use). The organization has 8066 authors who have published 25168 publications receiving 725033 citations. The organization is also known as: Jyväskylän yliopisto & Kasvatusopillinen korkeakoulu.

Physical activity as a preventive measure for coronary heart disease risk factors in early childhood

Abstract: Physical activity causes acute physiological and long-term adaptive responses in the body. It is a protective factor for coronary heart disease (CHD) in adults. It has been assumed that children younger than 8 years of age may be in general active enough and there would be hardly any relationships between physical activity and CHD risk factors in early childhood. One hundred and fifty-five children (age 4-7 years) participated in this physical activity study during three consecutive years. Physical activity was examined twice a year with a special-purpose physical activity diary. CHD risk factors were measured during annual health care visits in the Specific Turku Coronary Risk-Factor Intervention Project (STRIP). We found that physical activity was related to CHD risk factors in early childhood. Among the girls, low-activity playing was related to a higher BMI. At the mean age of 6 years, high-activity playing was negatively related to serum total cholesterol (r=-0.32*) and positively to the high-density lipoprotein (HDL)/total cholesterol ratio (r=0.37**). The negative relationship between high-activity playing and triglycerides was highest (r=-0.32*) at the mean age of six. Among 4-year-old boys, playing outdoors correlated positively with serum HDL cholesterol concentration (r=0.29*) and the HDL/total ratio (r=0.35**). At the age of 5 years, physically active playing correlated positively with systolic blood pressure (r=0.25*). Playing outdoors and high-activity playing already have important health-maintaining effects in 4-7-year-old children. These positive effects differ between genders. (*P<0.05 **P<0.01)

Bilateral and Unilateral Neuromuscular Function and Muscle Cross-Sectional Area in Middle-Aged and Elderly Men and Women

Abstract: Forty-eight healthy men (M) and women (W), divided into two different age groups, i.e., M50 yrs (range 44-57; n = 12), W50 yrs (range 43-57; n = 12), M70 yrs (range 59-75; n = 12), and W70 yrs (range 62-75; n = 12), volunteered as subjects for examination of muscle cross-sectional area (CSA), maximal voluntary forces, force-time curves, and electromyographic activity of the knee extensor muscles during bilateral and unilateral isometric contractions. The maximal bilateral knee extension force and the average CSA values in M50 were greater (p < .05) than in M70 and in W50 were greater (p < .05-.001) than those recorded for W70. The early forces in the force-time curve were greater (p < .05) for M50 than for M70 and in W50 were greater (p < .05) than in W70. The individual values of the CSA of the left and right quadriceps femoris (QF) correlated (p < .05-.001) with the individual values of maximal unilateral knee extension forces in M50 (r = .87 and r = .87), M70 (r = .61 and r = .80), W50 (r = .79 and r = .58), and W70 (r = .56 and r = .54). When the force values were related to the CSA of the muscle, W70 demonstrated a lower (p < .05) value than the other three groups. Maximal voluntary bilateral forces didn't differ from those of the summed unilateral forces, and the maximal integrated EMG values during the bilateral and unilateral contractions of the same leg were also the same. The results suggest that the decline in maximal strength with increasing age could be related to the decline in the CSA of the muscle, but in older people, especially women, strength decreases seemed to be multifactorial, including possibly a decrease in voluntary neural drive or changes in "qualitative" characteristics of the muscle tissue. Explosive strength may decrease with aging even more than maximal strength, suggesting that atrophying effects of aging may be greater on fast-twitch muscle fibers than on slow-twitch fibers and/or that the rate of neural activation of the muscles may also be influenced by aging. On the other hand, the central nervous system in a simple single joint isometric force production of the knee extensors seems to be capable of activation of the two bilateral QF muscle groups to the same degree in comparison to that of the unilateral activation only.

Isokinetic quadriceps and hamstring muscle strength and knee function 5 years after anterior cruciate ligament reconstruction: comparison between bone-patellar tendon-bone and hamstring tendon autografts

Abstract: Existing clinical studies have not proven which graft is to be preferred in anterior cruciate ligament (ACL) reconstruction. In recent years, bone-patellar tendon-bone and hamstring tendons have been the most frequently used graft types. Muscle strength deficit is one of the consequences after ACL reconstruction. The aim of this study was to evaluate possible differences in hamstring and quadriceps muscle strength and knee function 5 years after ACL reconstruction between the BPTB and the STG groups. The study group consisted of 288 patients (132 women, 156 men) with a unilateral ACL rupture who had received a BPTB (175 patients) or STG (113 patients) ACL reconstruction. Lower extremity concentric isokinetic peak extension and flexion torques were assessed at the angular velocities of 60°/s and 180°/s. The International Knee Documentation Committee (IKDC), the Tegner activity level, the Lysholm knee and the Kujala patellofemoral scores were also collected. Isokinetic quadriceps peak torque (percentage of the contralateral side) was 3.9% higher in the STG group than in the BPTB group at the velocity of 60°/s and 3.2% higher at the velocity of 180°/s and the isokinetic hamstring peak torque 2% higher in the BPTB group than in the STG group at the velocity of 60°/s and 2.5% higher at the velocity of 180°/s. In both groups the subjects had weaker quadriceps and hamstring muscle strength in the injured extremity compared with the uninjured one. In the single-leg hop test (according to the IKDC recommendations) there was a statistically significant difference (P = 0.040) between the groups. In the STG group, 68% of the patients had the single-leg hop ratio (injured vs. uninjured extremity) ≥90%, 31% of the patients 75–89% and 1% of the patients <75%, while in the BPTB group the corresponding percentages were 72, 21 and 7%. However, no statistically significant differences in clinical outcome were found between the groups as determined by the IKDC, Tegner activity level, Lysholm knee and Kujala patellofemoral scores.

Measurement of pion, kaon and proton production in proton–proton collisions at √s = 7 TeV

Abstract: The measurement of primary [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] production at mid-rapidity ([Formula: see text] 0.5) in proton-proton collisions at [Formula: see text][Formula: see text] 7 TeV performed with a large ion collider experiment at the large hadron collider (LHC) is reported. Particle identification is performed using the specific ionisation energy-loss and time-of-flight information, the ring-imaging Cherenkov technique and the kink-topology identification of weak decays of charged kaons. Transverse momentum spectra are measured from 0.1 up to 3 GeV/[Formula: see text] for pions, from 0.2 up to 6 GeV/[Formula: see text] for kaons and from 0.3 up to 6 GeV/[Formula: see text] for protons. The measured spectra and particle ratios are compared with quantum chromodynamics-inspired models, tuned to reproduce also the earlier measurements performed at the LHC. Furthermore, the integrated particle yields and ratios as well as the average transverse momenta are compared with results at lower collision energies.