Relationship Among Oxygenation, Myoelectric Activity, and Lactic Acid Accumulation in Vastus Lateralis Muscle During Exercise With Constant Work Rate

The purpose of this study was to determine whether oxygenation in localized working muscle depended on the muscle activity and on the lactic acidosis level. Seven healthy male subjects underwent the five 6-min cycling exercises with work rates of 50 watts (25.0 ± 5.0 % V˙O₂max), 100 watts (36.6 ± 6.2 % V˙O₂max), 150 watts (50.6 ± 7.7 % V˙O₂max), 200 watts (67.8 ± 6.9 % V˙O₂max), and 250 watts (82.9 ± 7.5 % V˙O₂max) while gas exchange parameters and blood lactate concentration (BL) were measured. We also measured oxygenated hemoglobin and myoglobin concentration (oxy-Hb/Mb) with continuous-wave near infrared spectroscopy (NIR) and surface myoelectric activity with surface electrodes (EMG). The NIR probe and electrodes were positioned on the vastus lateralis muscle of the right leg. The relative change in oxy-Hb/Mb was estimated by regarding oxy-Hb/Mb in the resting condition as 100 % and that obtained during thigh occlusion as 0 %. The mean values of oxy-Hb/Mb and integrated EMG (iEMG) were determined from 5′30″ to 6′00″ at each work rate. The percentage of oxy-Hb/Mb was sustained at the first two work rates corresponding to 25.0 ± 5.0 and 36.6 ± 6.2 % V˙O₂max and decreased slightly at 150 watts corresponding to 50.6 ± 7.7 % V˙O₂max, which was followed by a linear decrease at 200 and 250 watts corresponding to 67.8 ± 6.9 and 82.9 ± 7.5 % V˙O₂max. The iEMG, however, was increased slowly at 25.0 ± 5.0 to 50.6 ± 7.7 %V˙O₂max, and a rapid increment of the iEMG occurred at 67.8 ± 6.9 and 82.9 ± 7.5 % V˙O₂max. BL was sustained at 25.0 ± 5.0 to 50.6 ± 7.7 % V˙O₂max and increased linearly at 67.8 ± 6.9 and 82.9 ± 7.5 % V˙O₂max. There was a significant negative correlation for each subject between the percentage of oxy-Hb/Mb and iEMG (r = - 0.947 to - 0.993), between the percentage of oxy-Hb/Mb and BL (r = - 0.890 to - 0.982), and between the percentage of oxy-Hb/Mb and V˙O₂ (r = - 0.929 to - 0.994) These results indicated that oxygenated hemoglobin/myoglobin concentration measured with NIR reflected the muscle activity and the lactic acidosis.

Oxygenation, near infrared spectroscopy, iEMG, blood lactate.

References

• 01 Belardinelli R, Barstow T J, Porszasz J, Wasserman K. Change in skeletal muscle oxygenation during incremental exercise measured with near infrared spectroscopy.  Eur J Appl Physiol. 1995;  70 487-492
• 02 Belardinelli R, Barstow T J, Porszasz J, Wasserman K. Skeletal muscle oxygenation during constant work rate exercise.  Med Sci Sports Exerc. 1995;  27 512-519
• 03 Chance B, Dait T M, Chang C, Hamaoka T, Hagerman F. Recovery from exercise induced desaturation in the quadriceps muscle of elite competitive rowers.  Am J Physiol. 1992;  262 (Cell Physiol 31) c766-c775
• 04 Chance B, Nioka A, Kent J, McCully K, Fountain M, Greenfeld R, Holton G. Time resolved spectroscopy of hemoglobin and myoglobin in resting and ischemic muscle.  Anal Biochem. 1988;  174 698-707
• 05 Edwards R G, Lippold O CJ. The relationship between force and the integrated electrical activity in fatigued muscles.  J Physiol (Lond). 1956;  132 677-681
• 06 Hamaoka T, Albani C, Chance B, Iwane H. A new method for the evaluation of muscle aerobic capacity in relation to physical activity measured by near-infrared spectroscopy.  Med Sports Sci (Basel Karger). 1992;  37 421-429
• 07 Hamaoka T, Iwane H, Shimomitsu T, Katsumura T, Murase N, Nishio S, Osada T, Kurosawa Y, Chance B. Noninvasive measures of oxidative metabolism on working human muscle by near-infrared spectroscopy.  J Appl Physiol. 1996;  81 1410-1417
• 08 Hampson N B, Piantadoshi C A. Near infrared monitoring of human skeletal muscle oxygenation during forearm ischemia.  J Appl Physiol. 1988;  64 2449-2457
• 09 Hannerz J. Discharge properties of motor units in relation to recruitment order in voluntary contraction.  Acta Physiol Scand. 1974;  91 374-384
• 10 Jobsis F F. Noninvasive, infrared monitoring of cerebral and myocardial oxygen sufficiency and circulatory parameters.  Science. 1977;  198 1264-1267
• 11 Miyashita M, Kanehisa H, Nemoto I. EMG related to anaerobic threshold.  J Sports Med Phys Fitness. 1981;  21 209-217
• 12 McCully K, Iotti S R, Kendrick K, Wang Z, Posner J D, Leigh J, Chance B. Simultaneous in vivo measurements of HBO₂ saturation and PCr kinetics after exercise in normal humans.  J Appl Physiol. 1994;  77 5-10
• 13 Moritani T, Nagata A, Muro M. Electromyographic manifestations of muscular fatigue.  Med Sci Sports Exerc. 1982;  14 198-202
• 14 Nagata A, Muro M, Moritani T, Yoshida T. Anaerobic threshold determination by blood lactate and myoelectric signals.  Jpn J Physiol. 1981;  31 585-597
• 15 Petrofsky J S. Frequency and amplitude analysis of the EMG during exercise on the bicycle ergometer.  Eur J Appl Physiol. 1979;  41 1-15
• 16 Shiga T, Tanaka K, Nakase Y, Shida T, Chance B. Development of portable tissue oximeter using near infrared spectroscopy.  Med Biol Eng Comput. 1995;  33 622-626
• 17 Skinner J S, McLellan T H. The transition from aerobic to anaerobic metabolism.  Res Q Exerc Sports. 1980;  51 234-248
• 18 Stringer W, Wasserman K, Casaburi R, Porszasz J, Maehara K, French W. Lactic acidosis as a facilitator of oxyhemoglobin dissociation during exercise.  J Appl Physiol. 1994;  76 1462-1467
• 19 Viitasalo J T, Luhtanen P, Rahkila P, Rusko H. Electromyographic activity related to aerobic and anaerobic threshold in ergometer bicycling.  Acta Physiol Scand. 1985;  124 287-293
• 20 Wasserman K. Facilitation of oxygen consumption by lactic acidosis during exercise.  NIPS. 1991;  6 29-34
• 21 Wasserman K, Whipp B, Koyal S, Beaver W. Anaerobic threshold and respiratory gas exchange during exercise.  J Appl Physiol. 1973;  35 236-243
• 22 Wilson J R, Mancini D M, McCully K, Ferraro N, Lanoce V, Chance B. Noninvasive detection of skeletal muscle underperfusion with near-infrared spectroscopy in patients with heart failure.  Circulation. 1989;  80 1668-1674