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In another investigation, the gains in strength associated with 10 weeks of traditional resistance training were compared with those using SST (13). The subjects were 14 women, aged 19-45 years, who were randomly assigned to either regular or SST. Both groups trained three times a week during the study period, performing leg presses, leg curls, leg extensions, anterior lateral pull-downs, bench presses, seated rows, biceps curls, and triceps extensions. After 10 weeks, the traditional group had improved 1RM significantly more than the SST for the bench press (34% vs. 11%), the anterior lat pull-down (27% vs. 12%), the leg press (33% vs. 7%), leg extensions (56% vs. 24%) and leg curls (40% vs. 15%). The traditional group’s improvement in total weight lifted was significantly greater than that of the SST (39% vs. 15%). Although proponents of SST may feel lifting slowly is harder, the training responses do not add up to increased training gains.
Why Eccentric Contractions are Best for Muscle Hypertrophy.
So why is so important to emphasize explosive eccentric (ECC) contractions in your training routine. When comparing the amount of force that can be exerted by muscle contractions, ECC contractions yield higher force production than concentric (CON) contractions. When comparing maximal ECC contractions to maximal CON contractions, you can generally handle about 30-40% greater workloads during ECC contractions. Additionally, it has been reported that type II b fibers are more susceptible to eccentric exercise induced muscle damage than type I fibers, which may explain how fast ECC contractions induce muscle hypertrophy (23). The greater force producing capacity and higher degree of muscle damage can stimulate hypertrophy thru numerous mechanisms.
ECC Contractions and Muscle Protein Synthetic Rates
Animal and human studies have documented protein synthesis rates increase dramatically after ECC exercise, whereas protein synthesis rates after CON exercise are not elevated to the same extent. Wong and Boothe (14, 15) reported that ECC contractions induce muscle tissue hypertrophy through protein kinetics that are different from those of CON training. In their study, rats performed 24 electronically induced contractions of either plantar flexion (gastrocnemius) or extensions (tibialis anterior) every four days for 10 weeks. The goal of the study was to measure acute (12-17 hours) and post-exercise (36-41 hour’s) protein synthesis rates of identical contraction times for both CON and ECC training as well as tissue hypertrophy. Acute CON contractions increased gastrocnemius protein synthesis rates by 38 % but CON training failed to produce muscle hypertrophy despite an increase in protein synthesis. Contrary to CON training, acute ECC training resulted in a significantly higher protein synthesis rate 58% compared to 38%. Post-exercise protein synthesis rates from ECC but not CON exercise resulted in increased protein synthesis rates for 36-41 hours after exercise. ECC exercise produced muscle hypertrophy, whereas the similar CON protocol failed to produce muscle hypertrophy. Protein synthesis increased in the tibialis anterior (TA) after as little as 1 minute of total contraction duration (24 repetitions) by 30% and 8 minutes of total contraction time (192 repetitions) further increased TA protein synthesis by 45% above controls. Taken together, when CON and ECC contractions are performed with the similar total contraction times the data suggest that ECC exercise may play a larger role in muscle hypertrophy than CON exercise due to greater myofibrilliar protein breakdown after exercise. It can therefore be hypothesized that ECC training could result in a more anabolic environment due to increased protein degradation that is followed by rapid increases in protein synthesis. The greater increase in protein synthetic rates is speculated to occur because ECC exercise causes more damage, which results in the turnover of proteins, which must be replaced by new proteins. It is the damage produced from ECC exercise that stimulates immunological mediators to remove damaged tissue and repair damaged tissues by the incorporation of new proteins.
ECC training and Muscle Hypertrophy
ECC contractions are not just important for muscle hypertrophy, but some research indicates that their role seems to be essential (18, 19). Cote et al. (19) tested sedentary subjects using maximal CON only training on an isokinetic strength training routine for 10 weeks. No significant changes in mean skeletal muscle fiber area (i.e. no muscle hypertrophy) were observed. Cote speculated that the reason isokinetic resistance equipment fail to produce tissue hypertrophy was due to the absence of ECC contractions in the training routine. Hather et al. (17) documented that CON contractions without an ECC contraction failed to produce muscle tissue hypertrophy. Eight males trained unilateral leg extensions and leg press either with CON/ECC contractions or CON/CON (performed twice as many CON contractions) contractions for 4-5 sets and 6-12 reps two days a week for 19 weeks. Only the CON/ECC group showed an increase in mean fiber, whereas the group performing on CON contractions had no increase in muscle hypertrophy. Additionally, Hortobagyi et al. (20) had 15 males train either isokinetically CON or ECC for 12 weeks. Each subject trained with 4-6 sets of 8-12 reps; 3 times a week. At the end of 12 weeks, Type I fibers did not increase significantly in either group. The most interesting aspect of the study was that Type II fiber area increased 10 times more in the ECC group compared to the CON group. In a similar study, Higbie et al. (21) had 16 women train isokinetically either CON or ECC. The subjects trained 3 times a week using 3 sets of 10 reps for 10 weeks. Quadriceps cross-sectional area measured by magnetic resonance imaging increased more in the ECC-training group (6.6%) than in the CON-training group (5.0%). One may speculate that ECC training produced greater hypertrophy because it produces greater torque; however, ECC training at low training intensities has also proven to stimulate muscle hypertrophy.
Incorporating Explosive Lifting Into Your Routine
Therefore, now that the science of explosive training has been presented, you probably are going to want to start incorporating some lifts into your routine. Plyometrics are a great for incorporating explosive eccentric exercise. An excellent reading resource for incorporating plyometrics into your training routine is Donald Chu's, PhD. book, Jumping into Plyometrics. Plyometrics are an exercise technique that incorporates a rapid eccentric contraction followed by an explosive concentric contraction. I would suggest a 6 x 10 Method for hypertrophy and strength. That is 6 sets consisting of 10 explosive reps. This type of training will recruit the motor units that possess both Type IIB and Type IIA muscle fibers, respectively. This is very important since the aforementioned fibers have the greatest potential for growth. Emphasize explosive muscle actions (lifting) during the set, which maximally recruits the motor units mentioned above. Make the rest period short since you will be performing 10 reps per set, the total duration of the set is very short (~9 seconds). This is imperative since the force producing capabilities fast twitch motor decrease at any time longer than approximately 10 seconds. Rest periods should be approximately 1 minute between sets.
In conclusion, many bodybuilders and fitness oriented athletes alike would likely benefit from adding a few explosive type exercises to their training regimen such as plyometrics. In competitive athletics, when all other factors are equal, power is the deciding factor between winning and losing. The ability to generate concentric and eccentric force over a range of contraction velocities is often critical determinant of athletic success. For years, weight training was considered to slow an athlete down and make a athlete inflexible. Fifteen years ago, the University of Nebraska started training their football team using only the explosive Olympic lifts and the squat. Performing explosive lifts such as power cleans, jump squats, and depth jumps recruit entirely the fast twitch motor units. The training effect produced a stronger, faster, and more mobile athlete—and a winning record. Now, virtually all football teams incorporate Olympic lifts for explosive strength and power. Most bodybuilders never train with explosive eccentric contractions. The maximum force that a muscle can develop is attained during a rapid eccentric contraction. Incorporating these movements into your training routine will increase size and strength beyond traditional weight training.


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. im just lifting to put on weight at the moment. Id say weight training while not geared towards speed in my case has made me slightly faster anyway, definetely improved acceleration a tad. What do you do? How fast can you run a 100?
. 30 tries for the season here i come lol (its my first season of playing rugby (ever) in a lowish league so not actually that impressive lol).







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