Complex Training: a Brief Review

The effectiveness of plyometric training is well supported by research. Complex training has gained popularity as a training strategy combining weight training and plyometric training. Anecdotal reports recommend training in this fashion in order to improve muscular power and athletic performance. Recently, several studies have examined complex training. Despite the fact that questions remain about the potential effectiveness and implementation of this type of training, results of recent studies are useful in guiding practitioners in the development and implementation of complex training programs. In some cases, research suggests that complex training has an acute ergogenic effect on upper body power and the results of acute and chronic complex training include improved jumping performance. Improved performance may require three to four minutes rest between the weight training and plyometrics sets and the use of heavy weight training loads

The Effect of Concurrent Activation Potentiation During Fast Stretch Shortening Cycle Activity

This study evaluated the effect of remote voluntary contractions (RVC) on depth jump performance. Subjects performed the depth jump in a RVC condition and a condition without RVC (NO-RVC). Ground reaction force (GRF), impulse (I), and reactive strength index (RSI) were assessed with a force platform. Data were analyzed using a two way ANOVA. Analysis of GRF showed no significant main effects for RVC condition (p = 0.46) and no interaction for RVC condition and gender (p = 0.11). Analysis of I showed no significant main effects for RVC condition (p = 0.99) and no interaction for RVC condition and gender (p = 0.61). Analysis of RSI showed no significant main effects for RVC condition (p = 0.78) and no interaction for RVC condition and gender (p = 0.20). Remote voluntary contractions appear to offer no performance benefits for exercises such as the depth jump

The Effect of Concurrent Activation Potentiation on the Knee Extensor and Flexor Performance of Men and Women

This study evaluated the effect of remote voluntary contractions (RVC) during isometric and isokinetic knee flexion and extension tests and evaluated gender differences therein. Subject peak torque, rate of torque development, and power were assessed with a dynamometer in RVC and no RVC’s conditions. A two way mixed ANOVA with repeated measures for condition was used to evaluate the interaction between conditions and gender, and to assess the main effects. Main effects were evaluated with a paired samples t-test. Results revealed a significant interaction between all but one test condition and gender as well as significant main effects for all of the variables assessed (P ≤ 0.05). Men attained 9.2% to 19.7% greater performances in the RVC condition for all variables whilst women demonstrated no significant differences between test conditions

EMG Analysis of Concurrent Activation Potentiation

Purpose: This study evaluated the effect of remote voluntary contractions (RVC) on concentric isokinetic knee extensor and flexor peak torque, rate of torque development, power, and work, the activation of the affected muscles, and gender differences therein. Methods: Eleven men and 12 women were evaluated with EMG and isokinetic dynamometry during knee extension and flexion tests in RVC and baseline (NO-RVC) test conditions. The RVC condition included jaw clenching, hand gripping, and the Valsalva maneuver. A two-way mixed ANOVA with repeated measures for test condition was used to evaluate the main effects for each isokinetic measure, as well as the EMG of the prime movers, their antagonist, and the muscles involved in the RVC, and the interaction between test condition and gender. Results: Significant interactions between test condition and gender indicate differences in response to RVC during knee extension tests for power and work (P ≤ 0.05) and for knee flexion tests for peak torque and power (P ≤ 0.05). All subjects produced higher peak torque and power during knee extension in the RVC condition (P ≤ 0.05). Men produced a higher rate of torque development and work during knee extension (P ≤ 0.05) and a higher peak torque and power during knee flexion in the RVC condition (P ≤ 0.05). Prime mover activation was greater in the RVC condition for most tests (P ≤ 0.05). Women demonstrated lower bilateral flexor digitorum superficialis activation than men during all tests in the RVC condition (P ≤ 0.05). Conclusions: RVC increased the performance of several outcome variables assessed, which coincides with the concomitant increase in EMG of the prime movers

The Acute Time Course of Concurrent Activation Potentiation

This study evaluated the acute time course of the ergogenic effect of concurrent activation potentiation (CAP). Forty-two men and women, including CAP non-responders and responders, performed a 5 second isometric knee extension on a dynamometer with the use of remote voluntary contractions (RVC). Mean torque was assessed in seven 500 millisecond (ms) time periods. A two-way repeated measures ANOVA revealed significant main effects for time period (p ≤ 0.001), but no significant interaction between time period and CAP non-responders and responders (p \u3e 0.05). The ergogenic effects of CAP are accrued during the first 1000ms. Concurrent activation potentiation responders produce greater initial force than the CAP non-responders, without a concomitant acceleration in force decay throughout the time course

Quantifying the onset of the concentric phase of the force–time record during jumping

Thirteen college students performed a drop jump from height equal to their peak vertical jump, single leg jumps from the left and right legs, and a counter movement jump. Vertical ground reaction force (GRF) obtained via an AMTI force plate and video analysis of markers placed on the hip, knee, lateral malleolus, and fifth metatarsal were used to estimate reaction forces on the knee joint. One-way Repeated Measures ANOVA indicated no differences for knee joint reaction forces relative to body weight or peak GRF for any of the jumps (p \u3e 0.05). Average measures Intraclass Correlation Coefficients ranged from r = 0.90 to 0.97. Results indicate that peak GRF and knee joint reaction forces during the drop jump, counter movement jump, and single leg left and right leg jumps are reliable measures

Body Image as a Motivator and Barrier to Exercise Participation

Int J Exerc Sci 3(1): 14-24, 2010. This study examined self-reported relationships between motivations and barriers to exercise, frequency of exercise, and location of exercise to body image. The study surveyed 1044 students from a large Midwestern university. Respondents comprised of 689 (66.0%) females and 355 (34.0%) males with an age range of 17-55 years. Raw survey data were analyzed using independent content analysis. Most participants (76.8%) reported exercising while the remainder did not. Body image was a significant factor in determining the amount exercised for a majority of participants (58.3%), as well as the location of exercise for some (22.4%). Non-exercisers were satisfied with their overall appearance and did not identify body image as a significant barrier to exercise. However, non-exercisers, as well as exercisers, reported a desire to exercise more. Both exercisers (77.4%) and non- exercisers (90.9%) exercised more in the past and wished they exercised more currently (76.0% of exercisers and 88.8% of non-exercisers, respectively). These data show that body image was a motive to exercise amounts for exercisers, a barrier to exercise location for exercisers, but not a barrier to exercise for non-exercisers

GROUND AND KNEE JOINT REACTION FORCES DURING VARIATIONS OF PLYOMETRIC EXERCISES

Six Division-I athletes, who routinely used piyometric exercises, performed drop jumps from 46 and 61 cm, a pike jump, tuck jump, single leg jump, counter movement jump, squat jump, and a squat jump holding dumb ells equal to 30% of 1 RM squat. GRF obtained via an AMTI force plate and video analysis of mar1 0.05). Results indicate that although peak GRF forces of landing from plyometric exercise may not differ, the KRF do possibly due to variability in landing technIques

HAMSTRING ELECTROMYOGRAPHIC RESPONSE OF THE BACK SQUAT AT DIFFERENT KNEE ANGLES DURING CONCENTRIC AND ECCENTRIC PHASES

This study examined mean I-EMG for the hamstring group, during eccentric vs. concentric phases of the back squat at knee angles of 160-150, 140-130, 120-110 and 100-90. A 2X4 Repeated Measures ANOVA of the I-EMG hamstring activity revealed a significant interaction of contraction phase by angle (p.05). Closer analysis of each contraction phase via a One-way (angle) Repeated Measures ANOVA showed hamstring I-EMG during the eccentric contraction at 120-110 and 100-90 to be greater than 160-150 (p.05). In addition, there was no difference between 160-150 and 140-130 during the eccentric phase (p>.05). Furthermore, there were no differences found between mean I-EMG activity for any of the angles during concentric knee extension (p>.05)

IMPULSES AND GROUND REACTION FORCES AT PROGRESSIVE INTENSITIES OF WEIGHTLIFTING VARIATIONS

Five Division-I athletes who routinely performed the hang clean and hang snatch performed a single repetition of each at loads of 50, 60, 70, 80, and 90% of their 1 RM, with 5 minutes rest between each repetition. Movement impulses and peak GRF were evaluated on an AMTI force plate. Two-way ANOVA indicated impulses and peak GRF at 50% 1RM were lower than all other reps (