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Biomedical subjects

K Barlow

Publications and source records attributed to K Barlow.

8 recordsLinked to original sources

Energy & life.

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Cells

What is life?

All that science can do is to look into processes which, apparently first began to operate four billion years ago before any scientists were present to observe or comment. These processes fall into three categories--energetics, chemistry and life. Energetics and chemistry have been documented but what about life.

Biology

Milk.

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Animals

Effects of training at and above the lactate threshold on the lactate threshold and maximal oxygen uptake.

Thirty-three college women (mean age = 21.8 years) participated in a 5 d X wk-1, 12 week training program. Subjects were randomly assigned to 3 groups, above lactate threshold (greater than LT) (N = 11; trained at 69 watts above the workload associated with LT), = LT (N = 12; trained at the work load associated with LT) and control (C) (N = 10). Subjects were assessed for VO2max, VO2LT, VO2LT/VO2max, before and after training, using a discontinuous 3 min incremental (starting at 0 watts increasing 34 watts each work load) protocol on a cycle ergometer (Monark). Respiratory gas exchange measures were determined using standard open circuit spirometry while LT was determined from blood samples taken immediately following each work load from an indwelling venous catheter located in the back of a heated hand. Body composition parameters were determined before and after training via hydrostatic weighing. Training work loads were equated so that each subject expended approximately 1465 kJ per training session (Monark cycle ergometer) regardless of training intensity. Pretraining, no significant differences existed between groups for any variable. Post training the greater than LT group had significantly higher VO2max (13%), VO2LT (47%) and VO2LT/VO2max (33%) values as compared to C (p less than .05). Within group comparisons revealed that none of the groups significantly changed VO2max as a result of training, only the greater than LT group showed a significant increase in VO2LT (48%) (p less than .05), while both the = LT and greater than LT group showed significant increases in VO2LT/VO2max (= LT 16%, greater than LT 42% (p less than .05)).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Prediction of maximal effort bicycle ergometer endurance performance.

Fifteen competitive cyclists and 15 subjects not involved in competitive cycling were studied to determine the relationship between VO2max, lactate threshold (LT), fixed blood lactate concentrations, body composition parameters, and maximal effort bicycle ergometer performance. The subjects were assessed for VO2max, LT, VOLT, and VO2 associated with blood lactate concentrations of 3, 4, 5, and 6 mM/l (VO2 3 mM-VO2 6 mM/l), using an incremental protocol on the bicycle ergometer. Body composition was determined by underwater weighing. Subjects also completed two 10-min drop-off performance tests (starting at 70 rpm) at the same absolute power output (4.5 kg resistance, 1890 kgm/min) (ABS) and at the same relative power output (the highest power output completed for 3 min on the VO2max test) (REL). Metabolic measures and revolution scores were collected on a minute-by-minute basis during the performance tests. The results indicated that the competitive cyclists had higher VO2max (4.25 +/- 0.39 vs 3.50 +/- 0.54 l/min); VO2 LT (2.91 +/- 0.55 vs 1.66 +/- 0.49 l/min); VO2 3 mM, VO2 4 mM, VO2 5 mM, VO2 6 mM, VO2 LT/VO2max (68.5 +/- 11.2 vs 47.2 +/- 10.9 %); max resistance (5.70 +/- 0.56 vs 4.63 +/- 0.67 kg); and resistance at LT (3.57 +/- 0.70 vs 1.93 +/- 0.68 kg) as compared to the noncompetitive subjects (P less than 0.05). Correlational analysis revealed poor prediction between metabolic measures and the homogeneous cumulative rpm scores during the REL test.2+ subjects (r = 0.60 to 0.90).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult