Lactate and Heart Rate Variability Threshold during Resistance Exercise in the Young and Elderly

Abstract

This purpose of this study was to: 1) determine the intensity corresponding to anaerobic threshold (AT) during a discontinuous resistance exercise protocol in healthy young and elderly subjects by analyzing heart rate variability (HRV) and blood lactate (BL) and 2) investigate the effect of aging on these variables. A total of 28 individuals, 14 young and 14 elderly healthy men underwent one-repetition maximum (1RM) testing to determine maximum load on the leg press. Discontinuous resistance exercise testing was initiated at 10% of the 1RM with subsequent increases of 10%. The load corresponding to AT was approximately 30% 1RM in both groups. The determination of AT by HRV was associated with BL responses (p<0.01). While HRV indexes decreased with increasing of loads in both groups, the elderly had lower values at loads below AT (p<0.05). Additionally, BL increased sharply after the load corresponding to AT in both groups, although elderly subjects showed the lowest values (p<0.05). In conclusion, HRV is an effective tool for determining AT, which was approximately 30% 1RM under the testing procedures included in the present study. Furthermore, there was a marked change in autonomic function, with gradual vagal withdrawal followed by sympathetic activation. These responses were lower in elderly subjects.

Is Baseline Cardiac Autonomic Modulation Related to Performance and Physiological Responses Following a Supramaximal Judo Test?

“…Besides, recently Simoes et al [60] have shown a concordance between HRV and lactate regarding anaerobic threshold determination. Our results corroborate these previous investigations [4,58,59] in relation to the fact that initial parasympathetic reactivation (i.e.…”

Quantity of Aerobic Exercise Training for the Improvement of Heart Rate Variability in Older Adults

“…3 Other types of exercise were measured on the response to isometric exercise in autonomic modulation of the HR, but in older men, HR responses or the HRV (in the time domain) were not altered during sub-maximal isometric exercise. 20 Another study demonstrated, with increasing loads during a non-continuous resistance exercise protocol, a gradual withdrawal of the vagal tone followed by increased sympathetic activation. This shows the convergence of results of the effect to the other types of exercise.…”

The lactate and ventilatory thresholds in resistance training

“…Recent investigations have examined the physiological response to resistance exercise conducted at an intensity corresponding to LT. Several authors have reported higher LT values determined in incremental LP protocols than the LT values obtained during HS exercise in our study (24·8% and 25·4% 1RM for the algorithm adjustment and visual inspection methods, respectively): 28–32·2% 1RM (Barros et al ., ), 36·6% 1RM (Oliveira et al ., ), 31·0–36·7% 1RM (Moreira et al ., ), 31·6–32·3% 1RM (Rocha et al ., ), 30% 1RM (Simões et al ., ), 23·3–31·6% 1RM (de Sousa et al ., ), 27·1% 1RM (de Sousa et al ., ), 28% 1RM (Simões et al ., ), and ~30% de 1RM (Simões et al ., ). This could be because the exercise stimulus for the HS is greater than in the LP, given the larger number of muscle groups involved as a consequence of the work of synergistic and stabilizing muscles needed to maintain the position and support the loaded barbell.…”