Effect of chain wheel shape on crank torque, freely chosen pedal rate, and physiological responses during submaximal cycling.

The development of noncircular chain wheels for the enhancement of cycling performance has been in progress for a long time and continues apace. In this study we tested whether submaximal cycling using a non-circular (Biopace) versus a circular chain wheel resulted in lower peak crank torque at preset pedal rates as well as resulting in lower pedal rate and metabolic response at freely chosen pedal rate. Ten trained cyclists (mean+/-SD: 27+/-3 years of age, 182+/-4 cm tall, 77.

Performance following prolonged sub-maximal cycling at optimal versus freely chosen pedal rate.

It was tested whether cyclists perform better during all-out cycling following prolonged cycling at the pedal rate resulting in minimum oxygen uptake (VO(2)), i.e. the energetically optimal pedal rate (OPR) rather than at the freely chosen pedal rate (FCPR).

Estimation of VO2max from the ratio between HRmax and HRrest--the Heart Rate Ratio Method.

The effects of training and/or ageing upon maximal oxygen uptake ( VO(2max)) and heart rate values at rest (HR(rest)) and maximal exercise (HR(max)), respectively, suggest a relationship between VO(2max) and the HR(max)-to-HR(rest) ratio which may be of use for indirect testing of VO(2max). Fick principle calculations supplemented by literature data on maximum-to-rest ratios for stroke volume and the arterio-venous O(2) difference suggest that the conversion factor between mass-specific VO(2max) (ml.min(-1).

The yo-yo intermittent recovery test: physiological response, reliability, and validity.

Purpose: To examine the physiological response and reproducibility of the Yo-Yo intermittent recovery test and its application to elite soccer.

Methods: Heart rate was measured, and metabolites were determined in blood and muscle biopsies obtained before, during, and after the Yo-Yo test in 17 males. Physiological measurements were also performed during a Yo-Yo retest and an exhaustive incremental treadmill test (ITT).

Muscle fiber type distribution and nonlinear .VO(2)-power output relationship in cycling.

Purpose: We examined whether reported deviations from linearity of the oxygen uptake (.VO(2))-to-power output (W) relationship during intense cycling exercise correlated with the percentage Type II fibers in the exercising muscle.

Methods: Twelve trained young men with known fiber type distribution in the vastus lateralis muscle performed step-increment exercise (40 W.

Acyl-CoA binding protein expression is fiber type- specific and elevated in muscles from the obese insulin-resistant Zucker rat.

Accumulation of acyl-CoA is hypothesized to be involved in development of insulin resistance. Acyl-CoA binds to acyl-CoA binding protein (ACBP) with high affinity, and therefore knowledge about ACBP concentration is important for interpreting acyl-CoA data. In the present study, we used a sandwich enzyme-linked immunosorbent assay to quantify ACBP concentration in different muscle fiber types.

Acyl-coenzyme A binding protein expression is fibre-type specific in rat skeletal muscle but not affected by moderate endurance training.

The metabolic active form of free fatty acids, long-chain acyl-coenzyme A (lc-acyl-CoA), binds to its 10-kDa binding protein with high affinity. In the present study, we investigated the content of lc-acyl-CoA binding protein (ACBP) in different skeletal muscle fibre types. Soleus had the highest expression of ACBP (0.