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Effect of Functional Isometric Squats on Vertical Jump in Trained and Untrained Men
Berning, JM, Adams, KJ, DeBeliso, M, Sevene-Adams, PG, Harris, C, and Stamford, BA. Effect of functional isometric squats on vertical jump in trained and untrained men. J Strength Cond Res 24(9)2285-2289, 2010-Functional isometrics (FIs) combine dynamic and isometric muscle actions and may hyperstimulate the nervous system leading to an enhanced postactivation potentiation (PAP) and improved subsequent performance. The purpose of this study was to investigate the impact of an FI squat on the countermovement vertical jump (CMVJ) in resistance trained and untrained men. Thirteen trained men (age22.8 ± 3.2 years, mass90.0 ± 16.3 kg, and height178.9 ± 7.1 cm) and 8 untrained men (age28.5 ± 5.9 years, mass101.5 ± 23.0 kg, and height177.0 ± 4.8 cm) participated. On separate days, subjects performed CMVJs after 2 different warm-up conditions. The warm-up conditions consisted of either 5 minutes of low-intensity cycling or 5 minutes of low-intensity cycling plus a 3-second FI squat with 150% of their 1 repetition maximum (1RM). A 2 × 3 repeated-measures analysis of variance with Bonferroni post hoc revealed that when comparing the 2 warm-up conditions in the trained subjects, a significant increase (p < 0.05) in CMVJ occurred at 4 minutes (2.4 cm, +5.1%) post-FI squat. This increase was maintained when subjects were retested at 5 minutes post (2.6 cm, + 5.5%). No significant difference in CMVJ was detected in the untrained group (p = 0.49). Results support the addition of an FI squat performed at 150% of 1RM to a low-intensity cycling warm-up to enhance PAP in resistance trained but not in untrained men as measured by CMVJ. Practically, adding functional isometrics to a warm-up scheme may significantly enhance acute, short-term power output in resistance trained men.
Journal Article
METABOLIC DEMANDS OF “JUNKYARD” TRAINING: PUSHING AND PULLING A MOTOR VEHICLE
Junkyard training involves heavy, cumbersome implements and nontraditional movement patterns for unique training of athletes. This study assessed the metabolic demands of pushing and pulling a 1,960-kg motor vehicle (MV) 400 m in an all-out maximal effort. Six male, strength-trained athletes (29 ± 5 years; 89 ± 12 kg) completed 3 sessions. Sessions 1 and 2 were randomly assigned and entailed either pushing or pulling the MV. Oxygen consumption ( O2) and heart rate (HR) were measured continuously. Blood lactate was sampled immediately prior to and 5 minutes after sessions 1 and 2. Vertical jump was assessed immediately prior to and after sessions 1 and 2. During session 3 a treadmill O2max test was conducted. No significant differences (p > 0.05) in O2, HR, or blood lactate occurred between pushing and pulling efforts. O2 and HR peaked in the first 100 m, and from 100 m on, vehicle. O2 and HR averaged 65% and 96% of treadmill maximum values ( O2max = 50.3 ml·kg·min; HRmax = 194 b·min). Blood lactate response from the push and pull averaged 15.6 mmol·L, representing 131% of the maximal treadmill running value. Vertical jump decreased significantly pre to post in both conditions (mean = −10.1 cm, 17%). All subjects experienced dizziness and nausea. In conclusion, a 400-m MV push or pull is an exhausting training technique that requires a very high anaerobic energy output and should be considered an advanced form of training. Strength coaches must be aware of the ultra-high metabolic and neuromuscular stresses that can be imposed by this type of training and take these factors into consideration when plotting individualized training and recovery strategies.
Journal Article
Metabolic Demands of “Junkyard” Training: Pushing and Pulling a Motor Vehicle
Junkyard training involves heavy, cumbersome implements and nontraditional movement patterns for unique training of athletes. This study assessed the metabolic demands of pushing and pulling a 1,960-kg motor vehicle (MV) 400 m in an all-out maximal effort. Six male, strength-trained athletes (29 +/- 5 years; 89 +/- 12 kg) completed 3 sessions. Sessions 1 and 2 were randomly assigned and entailed either pushing or pulling the MV. Oxygen consumption (vo sub(2)) and heart rate (HR) were measured continuously. Blood lactate was sampled immediately prior to and 5 minutes after sessions 1 and 2. Vertical jump was assessed immediately prior to and after sessions 1 and 2. During session 3 a treadmill vo sub(2)max test was conducted. No significant differences (p < 0.05) in vo sub(2), HR, or blood lactate occurred between pushing and pulling efforts. vo sub(2) and HR peaked in the first 100 m, and from 100 m on, vo sub(2) and HR averaged 65% and 96% of treadmill maximum values (vo sub(2)max = 50.3 ml.kg super(-1).min super(-1); HRmax = 194 b.min super(-1)). Blood lactate response from the push and pull averaged 15.6 mmol.L super(-1), representing 131% of the maximal treadmill running value. Vertical jump decreased significantly pre to post in both conditions (mean = -10.1 cm, 17%). All subjects experienced dizziness and nausea. In conclusion, a 400-m MV push or pull is an exhausting training technique that requires a very high anaerobic energy output and should be considered an advanced form of training. Strength coaches must be aware of the ultra-high metabolic and neuromuscular stresses that can be imposed by this type of training and take these factors into consideration when plotting individualized training and recovery strategies.
Journal Article
I Am Potential
Patrick Henry Hughes was born with a rare genetic disorder that left him without eyes and physically disabled. But he was blessed with rare musical talentable to play the piano as a baby. Today, at age twenty, he is a nationally known pianist, singer, trumpeter, and marching-band member. With determined optimism, Hughes made I am potential\" his mantra, defying his disabilities at every turn. In I Am Potential, Hughes and his father share their extraordinary journey and describe the eight critical lessons at the heart of their success. Simply and candidly written, I Am Potential is an inspiration for anyone facing their own challenges.
eBook
Anabolic Androgenic Steroids: Use and Perceived Use in Nonathlete College Students
Objective: The authors investigated the use and perceived use of anabolic androgenic steroids (AAS) among nonathlete college students. Participants: The authors surveyed a sample of 485 nonathlete college students at a major metropolitan university. Methods: They administered a survey on use and perceived use of AAS to the students. Results: Forty-two participants (9%) reported using AAS (37 men, 5 women). Seniors were the most likely to use AAS (36%), and freshman the least likely (7%). Thirty-four percent of nonusers and 41% of users indicated they knew between 1 and 5 AAS users. Of the total sample, 36% perceived that 5% to 10% of nonathlete college students used AAS. Reasons for AAS use were because friends were using (7%), a desire to enhance physical appearance (45%), and a desire to increase physical performance (48%). Conclusions: These findings may have significant implications in planning strategic preventive educational programs, and health educators should target incoming college freshmen with the intent of dissuading AAS use.
Journal Article
The effect of smoking on energy expenditure and plasma catecholamine and nicotine levels during light physical activity
A number of studies have found that cigarette smoking causes an acute increase in resting energy expenditure, but the effect on energy expenditure during light physical activity is less clear. Since both smoking and activity have been shown to increase plasma catecholamines, these could produce additive effects on energy expenditure when smoking during light physical activity. In this study, the impact of cigarette smoking on energy expenditure, cardiovascular function, plasma nicotine and plasma catecholamine levels was determined in adult male subjects at rest and while engaged in light physical activity. Smoking at rest resulted in a 3.6% increase in energy expenditure above the resting baseline; whereas the increase in energy expenditure caused by smoking during light physical activity (compared with the light physical activity baseline) was 6.3%. This increase during light physical activity was significantly greater than the increase observed at rest (p < 0.025). As expected, plasma nicotine increased with smoking during both rest and light physical activity. An increase in plasma nicotine was associated with smoking during light physical activity. When this increase was adjusted as a covariate, the difference in smoking-related energy expenditure between light physical activity and rest disappeared, suggesting nicotine accounts for the effect. Plasma epinephrine and norepinephrine levels increased with smoking and showed a significantly greater increase during light physical activity compared to rest. Cigarette smoking caused a significantly greater increase in heart rate during light physical activity than it did while at rest, but there was no significant effect of smoking on mean blood pressure. It was concluded that there is enhanced energy expenditure associated with cigarette smoking during light physical activity when compared with smoking at rest which could be due in part to smoking-induced increases in circulating plasma catecholamines and perhaps nicotine.
Journal Article
