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

Abstract

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)

A Virtual Human Agent Model with Behaviour Based on Feeling Exhaustion

“…This is the maximal level of power that can be generated and sustained over longer periods without becoming exhausted, assuming no prior exercising. It is an asymptote of the hyperbolic power-duration curve defined by (GP -CP).t = W' that (as shown in various experiments) models the relationship between a constantly generated power GP (above the critical power CP) and the time t that this can be sustained; e.g., [7], [8], [9], [10], [11], [16]. Here W' is the total amount of work that can be spent above the critical power (the availble stored resources).…”

“…One of the issues addressed is how the generated effort is controlled and what is the role of feeling fatigue in this process; e.g., [5], [7], [8], [9], [10], [11], [12], [13], [14], [16]. The interplay of mind and body in this process is considered a crucial factor.…”

A virtual human agent model with behaviour based on feeling exhaustion

“…This is the maximal level of power that can be generated and sustained over longer periods without becoming exhausted, assuming no prior exercising. It is an asymptote of the hyperbolic power-duration curve defined by (GP − CP).t = W that (as shown in various experiments) models the relationship between a constantly generated power GP (above the critical power CP) and the time t that this can be sustained; e.g., [7][8][9][10][11][12]17]. Here W is the total amount of work that can be spent above the critical power (the available stored resources).…”

“…For long distance cyclists it is a challenge to train in an optimal fashion. The goal of training is to shift the basic critical power point upwards such that the person can deliver more power without having to pay back later (e.g., [9,17]). This can be accomplished by conducting training in intervals with a power level above the critical power point (high effort intervals), alternating with intervals with power level below the critical point (low effort intervals).…”

“…One of the issues addressed is how the generated effort is controlled and what is the role of feeling fatigue in this process; e.g., [5,[7][8][9][10][11][12][13][14][15]17]. The interplay of mind and body in this process is considered a crucial factor.…”