372
_______________________________________________________
Performance Measures, Blood Lactate and Plasma Ammonia as Indicators of Overwork in Elite Junior Weightlifters B. J. Warren1, M H. Stone1, I T Kearney2, S. I Fleck2, R. L. Johnson1, G. D. Wilson3, W. J. Kraemer4 'Human Performance Laboratory, Appalachian State University, Boone, NC, 28608 2Sport Science Division, United States Olympic Committee, Colorado Springs, CO, 80909 3Department of Health and Human Performance, Auburn University, Auburn, AL 36849 4Center for Sports Medicine, The Pennsylvania State University, University Park, PA, 16802
B. J. Warren, M. H. Stone, I. T Kearney, S. J. Fleck, R. L. Johnson, G. D. Wilson and W. J. Kraemer, Performance Measures, Blood Lactate and Plasma Ammonia as Indicators of Overwork in Elite Junior Weightlifters. Tnt J Sports Mcd, Vo113,No 5, pp 372—376, 1992.
Accepted: January 30, 1992
The effects of short-term overwork on performance measures, blood lactate, and plasma ammonia concentrations were examined in 28 elite junior weightlifters who participated in a 2 wk high volume resistance training camp. Performance testing (maximum effort vertical jump test and snatch lift) and blood chemistry analyses (ammonia and lactate) were conducted before (Ti) and after (T2) 7 d of high volume training (2—3 workouts/d). Blood samples were collected from an antecubital vein at rest, preexercise, 5 mm postexercise, and 15 mm postexercisc at Ti and T2. Results indicated a significant decrease from T 1 to T2 in the maximum effort vertical jump test while the snatch lift test yielded no difference across time. Blood lactate and ammonia concentrations were significantly lower at 5 mm postexercise at T2 while resting ammonia concentrations were significantly elevated at T2 compared to corresponding measures at Ti. These data
Although many parameters have been identified as indicative of the phenomenon of overwork/overtraining, there is little definitive research which depicts the exact mechanisms or time frame responsible for the overtrained state. Overwork has been described as an increase in training volume and/or intensity such that a decrease in performance results (30). Researchers have delineated a difference between short-term overwork in which recovery generally occurs within a few days of rest or reduced training and chronic overwork/overtraining, which requires several weeks or months for recovery to occur (21, 26, 28, 30). Two studies (14, 15) and a review (30) have reported symptoms indicative of short-term overwork during a one week sport camp, suggesting that overwork is related to frequent high volume, high intensity training with insufficient time for recovery. Both increases and decreases in lactate concentrations during, or following, exercise have been observed in association with overwork or fatigued conditions among athletes and other subjects (18, 21, 22, 30). Kuipers et al. (22) found increases in heart rate, ventilation, and blood lactate at given workloads when comparing laboratory conditions of induced overwork to sufficient rested states among endurance
athletes. Other studies have indicated that lactate concentrations may fall during chronically intense endurance exercise due to depletion of glycogen stores (8, 18).
suggest possible early symptoms of overwork at T2 (decrease in performance of the maximum effort vertical
Elevated ammonia concentrations during
jump test and the elevated resting ammonia concentrations); however, lower 5 mm postexercise concen-
work and recovery have also been associated with overwork (30). Bannister et al. (3) reported that elevated levels of ammonia interfere with tissue oxidative metabolism and promote anaerobiosis. The resulting decrease in tissue pH produces feelings associated with fatigue (2). Ammonia may also play a role in disruption of central nervous system regulation. Since ammonia crosses the blood-brain barrier (16), increases in peripheral blood ammonia may induce hyperammonemia leading to confusion and ataxia often associated with extreme
trations of lactate and ammonia at T2 indicated a positive adaptation to the 1 wk high volume resistance training period. Key words
Resistance training, weightlifting performance, overtraining
fatigue (3, 30).
In light of the association of these metabolites with fatigue and conditions of overwork, the present study was
designed to examine the effects of a 1 wk high volume re-
lnt.J.SportsMed. 13(1992)372—376 Georg Thieme Verlag Stuttgart New York
sistance training camp on blood lactate and ammonia concentrations of elite junior weightlifters. Aerobic training (5, 10, 12, 17). has been associated with the phenomenon of overwork . while relatively few studies have investigated overwork due to
Downloaded by: University of British Columbia. Copyrighted material.
Introduction
Abstract
Performance Measures, Blood Lactate and Plasma Ammonia as Indicators of Overwork
anaerobic type training (7, 28). Therefore, the purpose of the present investigation was to examine the effects of short-term
overwork on performance measures, blood lactate, and plasma ammonia concentrations due to anaerobic (Olympic weightlifting) type training.
mt. J. Sports Med. 13(1992) 373
snatch lift tests were administered, respectively. The maximum effort vertical jumps were filmed under optimal lighting conditions with a Panasonic WV 3250 video camera at 60 frames per s. The camera distance from the jumping platform was 8.35 m. A 2.54 cm reflective black dot was placed on the left greater trochanter of each subject to assist in digitizing the vertical displacement of each jump. Subjects were instructed to place their hands on their hips and to perform a maximal ef-
Subjects Twenty-eight subjects (= 17.3± 1.4 yrs) volunteered to participate in this investigation. Subjects were invited to participate in the project based on their performance at national and international weightlifting meets. All participants had placed first, second, or third in their age group and weight class at the 1988 American National Junior Championships. In addition, 6 of 10 weightlifters named to the American Junior National Team were participants in the investigation. The descriptive data for all subjects are summarized in Table 1. Prior to the initiation of the study, subjects were apprised of experimental risks and signed an approved informed consent document. Parental approval was obtained for those subjects under 18 years of age. Table I Sub)ect characteristics (n=28).
fort jump through the utilization of leg power only. Fifteen jumps were performed at 3 s intervals, with the cadence controlled by verbal cues. Each maximum effort jump was digitized from a standing reference point to peak vertical displacement (cm) utilizing a Peak Performance Motion Measurement System (Peak Performance Technologies, Inc., Englewood, CO). The snatch testing protocol consisted of the following: a) a snatch lift warm up of I set of 10 repetitions at 40% 1 RM; b) one set of snatches to exhaustion beginning at 50% 1 RM and adding 5 kg each repetition until the weight could not
be snatched successfully in two successive attempts. The cadence of the test was 1 snatch every 15 s controlled by timed verbal cues; and c) snatch pulls at 3 sets of 10 repetitions at 65% 1 RM with a cadence of one snatch every 4 s. Subjects rested for 1 mm between sets of snatch pulls.
Mean SEM
Variable
Age (yrs) hleight (cm) Body Mass (kg) Relative Fat (%) Fat Free Mass (kg) I RM Snatch (kg) 1 RM Clean and Jerk (kg) Lifting Experience (yrs)
17.3 0.26 167.2 0.53 67.8 2.25 6.2±0.42 63.5 1.97 94.2
3.63
120.2 4.44 2.8 0.28
Experimental Design A pre/posttest design was utilized to determine the performance and metabolic responses to a 7 d overwork protocol. Performance testing and blood chemistry analyses were conducted in Days 1 (TI) and 8 (T2), with training sessions conducted on Days 1 through 7. Blood samples were obtained from an antecubital vein under controlled laboratory
Blood Metabolite Measurements Lactate concentrations were determined in duplicate utilizing 25 p.1 of whole blood mixed with 50 p.1 of a pre-
pared preservative (32). Samples were refrigerated and analyzed within a 24 h period utilizing a Yellow Springs Model 23L Lactate Analyzer (Yellow Springs, OH). The intra-assay coefficient of variation was < 5%. Ammonia concentrations were obtained from heparinized plasma samples (4 ml). Samples were placed on ice and analyzed immediately using standard procedures of a diagnostic kit (Sigma Chemical Co, St. Louis, MO, Procedure No. l70-UV). Analyses were performed on a Beckman Model 34 Spectrophotometer (Irvine, CA). Intra-assay variability
was
_______________________________________________________
Performance Measures, Blood Lactate and Plasma Ammonia as Indicators of Overwork in Elite Junior Weightlifters B. J. Warren1, M H. Stone1, I T Kearney2, S. I Fleck2, R. L. Johnson1, G. D. Wilson3, W. J. Kraemer4 'Human Performance Laboratory, Appalachian State University, Boone, NC, 28608 2Sport Science Division, United States Olympic Committee, Colorado Springs, CO, 80909 3Department of Health and Human Performance, Auburn University, Auburn, AL 36849 4Center for Sports Medicine, The Pennsylvania State University, University Park, PA, 16802
B. J. Warren, M. H. Stone, I. T Kearney, S. J. Fleck, R. L. Johnson, G. D. Wilson and W. J. Kraemer, Performance Measures, Blood Lactate and Plasma Ammonia as Indicators of Overwork in Elite Junior Weightlifters. Tnt J Sports Mcd, Vo113,No 5, pp 372—376, 1992.
Accepted: January 30, 1992
The effects of short-term overwork on performance measures, blood lactate, and plasma ammonia concentrations were examined in 28 elite junior weightlifters who participated in a 2 wk high volume resistance training camp. Performance testing (maximum effort vertical jump test and snatch lift) and blood chemistry analyses (ammonia and lactate) were conducted before (Ti) and after (T2) 7 d of high volume training (2—3 workouts/d). Blood samples were collected from an antecubital vein at rest, preexercise, 5 mm postexercise, and 15 mm postexercisc at Ti and T2. Results indicated a significant decrease from T 1 to T2 in the maximum effort vertical jump test while the snatch lift test yielded no difference across time. Blood lactate and ammonia concentrations were significantly lower at 5 mm postexercise at T2 while resting ammonia concentrations were significantly elevated at T2 compared to corresponding measures at Ti. These data
Although many parameters have been identified as indicative of the phenomenon of overwork/overtraining, there is little definitive research which depicts the exact mechanisms or time frame responsible for the overtrained state. Overwork has been described as an increase in training volume and/or intensity such that a decrease in performance results (30). Researchers have delineated a difference between short-term overwork in which recovery generally occurs within a few days of rest or reduced training and chronic overwork/overtraining, which requires several weeks or months for recovery to occur (21, 26, 28, 30). Two studies (14, 15) and a review (30) have reported symptoms indicative of short-term overwork during a one week sport camp, suggesting that overwork is related to frequent high volume, high intensity training with insufficient time for recovery. Both increases and decreases in lactate concentrations during, or following, exercise have been observed in association with overwork or fatigued conditions among athletes and other subjects (18, 21, 22, 30). Kuipers et al. (22) found increases in heart rate, ventilation, and blood lactate at given workloads when comparing laboratory conditions of induced overwork to sufficient rested states among endurance
athletes. Other studies have indicated that lactate concentrations may fall during chronically intense endurance exercise due to depletion of glycogen stores (8, 18).
suggest possible early symptoms of overwork at T2 (decrease in performance of the maximum effort vertical
Elevated ammonia concentrations during
jump test and the elevated resting ammonia concentrations); however, lower 5 mm postexercise concen-
work and recovery have also been associated with overwork (30). Bannister et al. (3) reported that elevated levels of ammonia interfere with tissue oxidative metabolism and promote anaerobiosis. The resulting decrease in tissue pH produces feelings associated with fatigue (2). Ammonia may also play a role in disruption of central nervous system regulation. Since ammonia crosses the blood-brain barrier (16), increases in peripheral blood ammonia may induce hyperammonemia leading to confusion and ataxia often associated with extreme
trations of lactate and ammonia at T2 indicated a positive adaptation to the 1 wk high volume resistance training period. Key words
Resistance training, weightlifting performance, overtraining
fatigue (3, 30).
In light of the association of these metabolites with fatigue and conditions of overwork, the present study was
designed to examine the effects of a 1 wk high volume re-
lnt.J.SportsMed. 13(1992)372—376 Georg Thieme Verlag Stuttgart New York
sistance training camp on blood lactate and ammonia concentrations of elite junior weightlifters. Aerobic training (5, 10, 12, 17). has been associated with the phenomenon of overwork . while relatively few studies have investigated overwork due to
Downloaded by: University of British Columbia. Copyrighted material.
Introduction
Abstract
Performance Measures, Blood Lactate and Plasma Ammonia as Indicators of Overwork
anaerobic type training (7, 28). Therefore, the purpose of the present investigation was to examine the effects of short-term
overwork on performance measures, blood lactate, and plasma ammonia concentrations due to anaerobic (Olympic weightlifting) type training.
mt. J. Sports Med. 13(1992) 373
snatch lift tests were administered, respectively. The maximum effort vertical jumps were filmed under optimal lighting conditions with a Panasonic WV 3250 video camera at 60 frames per s. The camera distance from the jumping platform was 8.35 m. A 2.54 cm reflective black dot was placed on the left greater trochanter of each subject to assist in digitizing the vertical displacement of each jump. Subjects were instructed to place their hands on their hips and to perform a maximal ef-
Subjects Twenty-eight subjects (= 17.3± 1.4 yrs) volunteered to participate in this investigation. Subjects were invited to participate in the project based on their performance at national and international weightlifting meets. All participants had placed first, second, or third in their age group and weight class at the 1988 American National Junior Championships. In addition, 6 of 10 weightlifters named to the American Junior National Team were participants in the investigation. The descriptive data for all subjects are summarized in Table 1. Prior to the initiation of the study, subjects were apprised of experimental risks and signed an approved informed consent document. Parental approval was obtained for those subjects under 18 years of age. Table I Sub)ect characteristics (n=28).
fort jump through the utilization of leg power only. Fifteen jumps were performed at 3 s intervals, with the cadence controlled by verbal cues. Each maximum effort jump was digitized from a standing reference point to peak vertical displacement (cm) utilizing a Peak Performance Motion Measurement System (Peak Performance Technologies, Inc., Englewood, CO). The snatch testing protocol consisted of the following: a) a snatch lift warm up of I set of 10 repetitions at 40% 1 RM; b) one set of snatches to exhaustion beginning at 50% 1 RM and adding 5 kg each repetition until the weight could not
be snatched successfully in two successive attempts. The cadence of the test was 1 snatch every 15 s controlled by timed verbal cues; and c) snatch pulls at 3 sets of 10 repetitions at 65% 1 RM with a cadence of one snatch every 4 s. Subjects rested for 1 mm between sets of snatch pulls.
Mean SEM
Variable
Age (yrs) hleight (cm) Body Mass (kg) Relative Fat (%) Fat Free Mass (kg) I RM Snatch (kg) 1 RM Clean and Jerk (kg) Lifting Experience (yrs)
17.3 0.26 167.2 0.53 67.8 2.25 6.2±0.42 63.5 1.97 94.2
3.63
120.2 4.44 2.8 0.28
Experimental Design A pre/posttest design was utilized to determine the performance and metabolic responses to a 7 d overwork protocol. Performance testing and blood chemistry analyses were conducted in Days 1 (TI) and 8 (T2), with training sessions conducted on Days 1 through 7. Blood samples were obtained from an antecubital vein under controlled laboratory
Blood Metabolite Measurements Lactate concentrations were determined in duplicate utilizing 25 p.1 of whole blood mixed with 50 p.1 of a pre-
pared preservative (32). Samples were refrigerated and analyzed within a 24 h period utilizing a Yellow Springs Model 23L Lactate Analyzer (Yellow Springs, OH). The intra-assay coefficient of variation was < 5%. Ammonia concentrations were obtained from heparinized plasma samples (4 ml). Samples were placed on ice and analyzed immediately using standard procedures of a diagnostic kit (Sigma Chemical Co, St. Louis, MO, Procedure No. l70-UV). Analyses were performed on a Beckman Model 34 Spectrophotometer (Irvine, CA). Intra-assay variability
was
