Derek Bunker

Neuromuscular Activity During Whole-Body Vibration of Different Amplitudes and Footwear Conditions: Implications for Prescription of Vibratory Stimulation

Marín, PJ, Bunker, D, Rhea, MR, and Ayllón, FN. Neuromuscular activity during whole-body vibration of different amplitudes and footwear conditions: implications for prescription of vibratory stimulation. J Strength Cond Res 23(8): 2311-2316, 2009-This study investigated the magnitude of whole-body vibration (WBV) at 30 Hz induced in surface electromyography root-mean-square (EMGrms) signals of different amplitudes and footwear conditions of unloaded isometric half squat (100o). For this purpose, 10 healthy and active males (age 28.7 ± 4.6 yr; height 180 ± 5.9 cm; and weight 90 ± 13.4 kg) volunteered to participate in this study. Subjects were exposed to the WBV treatment using a vibration platform (FreeMotion Fitness iTonic). The subjects were exposed randomly to 4 different treatments of WBV: with shoes 2 mm amplitude, without shoes 2 mm, with shoes 4 mm, and without shoes 4 mm. The EMGrms signals were recorded from the vastus lateralis and the gastrocnemius medialis muscle during the different conditions. The WBV treatments resulted in a significantly higher (p ≤ 0.05) EMGrms compared with unloaded isometric half squat (without WBV). The WBV treatment that induced the highest EMGrms signals of the vastus lateralis was during the amplitude of 4 mm without shoes (+62.7%; p < 0.01), whereas 4 mm with shoes induced the highest EMGrms signals of the gastrocnemius medialis (+142.7%; p < 0.01). These data suggest that wearing shoes does alter the neuromuscular response to WBV stimuli, and exercise professionals should consider such differences when using WBV to target neuromuscular activation of such muscle groups. In this study, the magnitude of the WBV effect was clearly higher with the amplitude 4 mm versus 2 mm for the vastus lateralis muscle and gastrocnemius medialis muscle. The vastus lateralis showed the greatest activity without shoes and at amplitude of 4 mm. The maximal activation for the gastrocnemius medialis was measured with shoes at 4 mm.

Effect of itonic Whole-body Vibration on Delayed-onset Muscle Soreness Among Untrained Individuals

Rhea, MR, Bunker, D, Marín, PJ, and Lunt, K. Effect of iTonic whole-body vibration on delayed-onset muscle soreness among untrained individuals. J Strength Cond Res 23(6): 1677-1682, 2009-Attempts to reduce or eliminate delayed-onset of muscle soreness are important as this condition is painful and debilitating. The purpose of this study was to examine the effectiveness of whole-body vibration (WBV) massage and stretching exercises at reducing perceived pain among untrained men. Sixteen adult men (age, 36.6 ± 2.1 yr) volunteered to perform a strenuous exercise session consisting of resistance training and repeated sprints. Subjects were randomly assigned to 1 of 2 recovery groups: a group performing WBV stretching sessions or a stretching group performing static stretching without vibration. Both groups performed similar stretches, twice per day for 3 days after the workout. The vibration group performed their stretches on the iTonic platform (frequency, 35 Hz; amplitude, 2 mm). Perceived pain was measured at 12, 24, 48, and 72 hours postworkout. Statistical analyses identified a significantly lower level of reported perceived pain at all postworkout measurement times among the WBV group (p < 0.05). No difference existed at the preworkout measurement time. The degree of attenuation of pain ranged from 22-61%. These data suggest that incorporating WBV as a recovery/regeneration tool may be effective for reducing the pain of muscle soreness and tightness after strenuous training.

Effects of linear vs. daily undulatory periodized resistance training on maximal and submaximal strength gains.

Miranda, F, Simão, R, Rhea, M, Bunker, D, Prestes, J, Leite, RD, Miranda, H, de Salles, BF, and Novaes, J. Effects of linear vs. daily undulatory periodized resistance training on maximal and submaximal strength gains. J Strength Cond Res 25(7): 1824-1830, 2011—The objective of this study was to verify the effect of 2 periodized resistance training (RT) methods on the evolution of 1-repetition maximum (1RM) and 8RM loads. Twenty resistance trained men were randomly assigned to 2 training groups: linear periodization (LP) group and daily undulating periodization (DUP) group. The subjects were tested at baseline and after 12 weeks for 1RM and 8RM loads in leg press (LEG) and bench press (BP) exercises. The training program was performed in alternated sessions for upper (session A: chest, shoulder and triceps) and lower body (session B: leg, back and biceps). The 12-week periodized training was applied only in the tested exercises, and in the other exercises, 3 sets of 6-8RM were performed. Both groups exhibited significant increases in 1RM loads on LEG and BP, but no statistically significant difference between groups was observed. The same occurred in 8RM loads on LEG and BP. However, DUP group presented superior effect size (ES) in 1RM and 8RM loads for LEG and BP exercises when compared to the LP group. In conclusion, periodized RT can be an efficient method for increasing the strength and muscular endurance in trained individuals. Although there was no statistically significant difference between periodization models, DUP promoted superior ES gains in muscular maximal and submaximal strength.

INFLUENCE OF MODERATELY INTENSE STRENGTH TRAINING ON FLEXIBILITY IN SEDENTARY YOUNG WOMEN

Santos, E, Rhea, MR, Simão, R, Dias, I, Freitas de Salles, B, Novaes, J, Leite, T, Blair, JC, and Bunker, DJ. Influence of moderately intense strength training on flexibility in sedentary young women. J Strength Cond Res 24(11): 3144-3149, 2010-The present study is the first to examine whether moderately intense resistance training improves flexibility in an exclusively young, sedentary women population. Twenty-four, young, sedentary women were divided into 3 groups as follows: agonist/antagonist (AA) training group, alternated strength training (AST) group, or a control group (CG). Training occurred every other day for 8 weeks for a total of 24 sessions. Training groups performed 3 sets of 10 to 12 repetitions per set except for abdominal training where 3 sets of 15 to 20 reps were performed. Strength (1 repetition maximum bench press) and flexibility were assessed before and after the training period. Flexibility was assessed on 6 articular movements: shoulder flexion and extension, horizontal shoulder adduction and abduction, and trunk flexion and extension. Both groups increased strength and flexibility significantly from baseline and significantly when compared with the CG (p ≤ 0.05). The AST group increased strength and flexibility significantly more than the AA group (p ≤ 0.05) in all but one measurement. This study shows that resistance training can improve flexibility in young sedentary women in 8 weeks.

THE USE OF WHOLE-BODY VIBRATION AS A GOLF WARM-UP

Bunker, DJ, Rhea, MR, Simons, T, and Marin, PJ. The use of whole-body vibration as a golf warm-up. J Strength Cond Res 25(2): 293-297, 2011-The purpose of this case series was to test the effectiveness of an active warm-up for recreational golfers using a whole-body vibration (WBV) platform. The variables that the warm-up tested for were increased flexibility, power, and golf performance. Ten adult men (age: 45 ± 15 yr) volunteered to perform their personal warm-up and record 7 of their golf swings. They then participated in an active warm-up involving flexibility exercises on the iTonic WBV platform and then recorded 7 more golf swings. The settings for the iTonic WBV platform were set to a frequency of 50 Hz and an amplitude of 2 mm, and each exercise was performed for 30 seconds. Eight different exercises were used for this warm-up. Significant changes (p < 0.05) were measured after the WBV warm-up in the following variables: sit and reach, ball speed, carry distance, and total distance. In a subgroup of subjects less than 45 years of age (n = 5), results mimicked those reported for the entire group in that both flexibility and power measures improved significantly. Subjects older than 45 years (n = 5) did not significantly (p < 0.05) improve in power measures but did improve sit and reach similarly to the younger group. These data suggest that a profound increase in the flexibility and power output of individual golfers occurs when a WBV warm-up bout is performed.

A Description and Comparison of Cardiorespiratory Fitness Measures in Relation to Pitching Performance Among Professional Baseball Pitchers

The purpose of this study is to provide descriptive and comparative information regarding the cardiorespiratory fitness of professional baseball pitchers. Twenty-four (n = 24) major league (ML) baseball pitchers (starters n = 14; relievers n = 10) over seven seasons (2007–2013) were evaluated. A modified Bruce protocol and the CardioCoach™ CO2 metabolic analyzer were used to estimate VO2 max and anaerobic threshold (AT) at the beginning of each season. Performance data from each season was utilized to draw inference about pitching performance. One-way Analysis of Variance (ANOVA) was used to compare Starting (S) and Relief (R) pitchers above/below the group mean for VO2 max and AT. Pearson product moment correlations were also used to examine relationships between cardiorespiratory fitness and performance. Significant differences in performance were discovered between S pitchers above/below the overall group mean for VO2 max. (p ≤ 0.05) and for AT in Walks plus Hits per Inning Pitched (WHIP) (p ≤ 0.05) and Earned Run Average (ERA) (p ≤ 0.05). Significant relationships between VO2 max and Walks per 9 Innings (BB/9) (p ≤ 0.05), Home Runs per 9 innings (HR/9) (p ≤ 0.05), Wins (W) (p ≤ 0.05), Fielding Independent Pitching (FIP) (p ≤ 0.01), Strikeouts (K) (p ≤ 0.01), Hits per 9 innings (H/9) (p ≤ 0.01), Strikeouts per 9 innings (K/9) (p ≤ 0.01), ERA (p ≤ 0.01), and WHIP (p ≤ 0.01). Low, but significant, correlations were discovered between AT and WHIP (p ≤ 0.05) and ERA (≤0.05). CONCLUSION: Higher aerobic capacity appears to be more influential for S than R pitchers. Strength and conditioning practitioners should ensure that pitchers, especially S pitchers at the ML level, perform sufficient and appropriate endurance training to support pitching performance.