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Tuesday, March 20, 2012

Super Bad James - Dynomite


Super Bad James - Dynomite 
5-D Comics
Issue 01 (Of 5)
English / 32 Pages / 2005 / CBR Format / 14 MB Size

Domino Lady


Domino Lady 
Moonstone Comics
By Nancy Holder and Shawn Van Briesen 
Issue 04
English / 32 Pages / 2010 / 2 Covers / CBR Format / 14 MB Size

Doom Patrol


Doom Patrol 
DC Comics
By John Byrng and Dave Hazlewood 
Issue 08
2010 / CBR Format / 32 Pages / English / 15.1 MB Size

Forgetless


Forgetless 
Live To See Last Call
Image Comics
By Spencer, Forbes and Zarcone 
Issue 01 (Of 5)
2009 / CBR Format / 49 Pages / English / 15.2 MB Size

Grim Fairy Tales - Escape From Wonderland


Grim Fairy Tales
Escape From Wonderland 
Zenescope Comics
By Gregory, Leister and Ruffino 
Issue 06
2010 / CBR Format / English / 2 Covers / 36 pages / 15.5 MB Size

Michael Turner's Soulfire


Michael Turner's
Soulfire 
Volume 2
Aspen Comics
By J.T. Krul, Jason Fabok and John Starr 
Issue 02
August 2010 / CBR Format / 49 Pages / English / 11.4 MB Size

Tank Girl - Dirty Helmets


A Very Special Special 
Tank Girl - Dirty Helmets
Image Comics
By Alan C. Martin and Rufus Dayglo 
2010 / PDF Format / English / 36 pages / 32.3 MB Size

Doom Patrol


Doom Patrol 
DC Comics
By Giffen, Clark, Randall and Livesay
Issue 08
June 2010 / CBR Format / 32 Pages / English / 11.6 MB Size

Michael Turner's Soulfire


Soulfire
Aspen Comic
By Michael Turner
Issue 03
2010 / CBR Format / 49 Pages / English / 10.6 MB Size

Street Fighter Legends - Ibuki


Street Fighter Legends - Ibuki
Volume 1
Udon Comics / Capcom 
By Jim Zubkavich and Omar Dogan 
Issue 01 
March 2010 / CBR Format / English / 24 pages / 21.5 MB Size

What Is Creatine


Introduction


During the past decade, the nutritional supplement creatine monohydrate has been gaining popularity exponentially, with reported annual  sales in the U.S alone climbing from $50 million in 1996 (Bamberger, 1998) to over $400 million during 2001 (Metzl et al., 2001). Creatine supplementation (CrS) first gained popular attention in the early 1990s, after high profile Olympic athletes competing in sprint and power events at the Barcelona Olympic Games believed their performance had benefited from CrS (Anderson, 1993). Since this time creatine (Cr) has become one of the most widely used nutritional supplements with an estimated worldwide consumption of 2.7 million kilograms (Williams et al., 1999). Recently, many athletes and teams have implemented oral CrS in an effort to enhance sports performance, as CrS is not presently (October, 2003) on the banned substance list by the International Olympic Committee (2003). Thus, using this supplement would not constitute anything illegal or unethical on behalf of the athlete or coach. Consequently, Cr has risen to the top of the modern athletes shopping list. This article does not purport to be an exhaustive review of all related published literature, however, it is the purpose of this paper  to outline evidence presented and report on the usefulness of CrS as a performance-enhancing aid by identifying potential ergogenic effects related to this supplement. Readers are referred to other reviews for aspects of this topic that may not be addressed by this article (Volek and Kraemer, 1996; Mujika and Padilla, 1997; Williams and Branch, 1998; Jacobs,1999; Wyss and Kaddurah-Daouk, 2000; Lemon, 2002). A French scientist named Chevreul is credited124 Creatine supplementation and exercise performance with first discovering Cr in 1832 (Williams et al.,1999), however, it was not until 1926 that scientists quantified Cr storage and retention in the body (Chanutin, 1926). Cr is a compound that is both made within the body from amino acids and obtained through diet. Most of the body’s Cr is stored within skeletal muscle where it plays a role in metabolism, with the daily turnover of Cr for the average sized person of about 2 g (for review see Wyss and Kaddurah-Daouk, 2000). Williams and Branch (1998) suggest that the adenosine triphosphate-phosphocreatine (ATP-PCr) energy system has the greatest power potential. Muscle stores of PCr may split and release energy for rapid resynthesis of ATP, although the supply of PCr is limited, with the combined total ATP and PCr capable of sustaining all out maximal effort exercise lasting up to 5 to 10 seconds (Williams and Branch, 1998). Therefore, fatigue may be attributed to the rapid decrease in PCr. Generation of peak anaerobic power and anaerobic capacity in short-term, highintensity exercise may be dependent upon endogenous levels of ATP and PCr, particularly, PCr as a means to rapidly regenerate the limited intramuscular supply of ATP for anaerobic capacity (Williams and Branch 1998). Thus, an increase in muscle total creatine (TCr) through exogenous CrS may provide an ergogenic effect by enhancing the rate of ATP synthesis during intermittent, highintensity, short-duration exercise and by improving the rate of PCr resynthesis during recovery (Snow et al., 1998). This contention is supported by the findings of Kurosawa et al. (2003) who evaluated the rate of ATP synthesis through PCr hydrolysis and glycolysis and mean power output during a 10 second maximal dynamic handgrip exercise (Ex10) using 31-phosphorus magnetic resonance spectroscopy before and after CrS (30 g· day - 1 for 14 days). ATP synthesis rate through PCr hydrolysis positively correlated with mean power output during Ex10 in all subjects after CrS (r = 0.58, p < 0.05). The authors concluded that a daily dose of 30g CrS for 14 days improved APT synthesis through PCr  hydrolysis and mean power output during shortterm, maximal exercise. Moreover, it is strongly indicated that an improvement in performance during Ex10 was associated with the increased PCr availability for the synthesis of ATP. The body has several different ways in which it restores ATP. As previously stated, energy is released when one of the phosphates in ATP is cleaved off. When this happens, ATP becomes adenosine diphosphate (ADP). Returning ADP to its high-energy state of ATP by adding another phosphate group to it can then recycle ADP. One such ATP producing system is glycolysis, which is  achieved anaerobically. Another system that the body extracts energy from is oxidative phosphorylation, which incorporates oxygen to yield ATP (for review see Mommaerts, 1969). The degree to which skeletal muscle will use PCr may be intensity and duration dependant. When intensity exceeds the power of the aerobic system the muscle begins to rely on the anaerobic system, which includes the use of PCr and muscle glycogen as fuels. Consequently, during the most intense periods of exercise or sport, the muscle will tax the PCr store most highly (Wyss and Kaddurah-Daouk, 2000). Therefore, some have argued that CrS may benefit certain athletes in particular sports (Dawson et al., 1995;  Meir, 1995; Schnedeider et al., 1997; Izquierdo et al., 2002). CrS has been suggested as a means to "load" the muscle with Cr and increase storage of PCr (Dawson et al., 1995;  Snow et al., 1998; Finn et al., 2001). Theoretically, this would serve to improve the ability to produce energy during explosive, highintensity exercise bouts and/or enhance the ability to recover from intense exercise. In support of the contention research has shown that CrS increases intramuscular PCr concentrations (Harris et al.,1992; Vandenberghe et al., 1997;  McKenna et al., 1999; Stout et al., 2000). Furthermore, the CrSrelated increase in PCr concentration may allow a ‘mopping up’ the acid producing hydrogen ions produced during the breakdown of ATP and other anaerobic processes (Vandenberghe et al., 1997; Stout et al., 2000). Therefore, PCr may contribute to the maintenance of optimal pH levels within the muscle and allows continued performance with minimal fatigue (for review see Volek and Kraemer, 1996).


WHAT DOES THE RESEARCH INDICATE?


Following the first reports by Harris et al. (1992), that PCr content in human muscle can increase up to 50% following daily CrS (5 g Cr monohydrate 4-6 × day for ³ 2 days), a number of studies have examined the effects of CrS on muscle metabolism and/or high-intensity exercise performance. Studies that have measured muscle total creatine (TCr) (phosphocreatine + creatine) have reported an elevation in TCr after CrS involving loading phases of 20-30  g· day -1 for 3-6 days. Some studies found that both resting TCr and PCr content increased (McKenna et al., 1999; Smith et al., 1999; Kurosawa et al., 2003), whereas others reported significant increases in only TCr (Greenhaff et al., 1994; Becque et al., 2000) or PCr (Smith et al., 1998; Stout et al., 2000).Theoretically, an increase in TCr stores may provide an ergogenic effect during high intensity exercise by enhancing the rate of ATP synthesis during contraction and by improving the rate of PCrBird 125 resynthesis during recovery, which may be beneficial for repeated sprint activity. A recent investigation by Mujika et al. (2000) supports such a contention, concluding that acute CrS favourably affected repeated sprint performance and limited the decay in jumping ability in highly trained soccer players. However, on the whole, experimental evidence supporting an ergogenic effect for CrS is  somewhat mixed. Several studies have demonstrated improved high-intensity exercise performance after  CrS (Dawson et al., 1995; Meir, 1995; Jacobs et al., 1997; Vandenberghe et al., 1997; Volek et al., 1999; Mujika et al., 2000), whereas others have reported no beneficial effects (Barnett et al., 1995; Snow et al., 1998; Deutekom et al., 2000; Gilliam et al.,2000; Finn et al., 2001; Syrotuik et al., 2001; Biwer et al., 2003). 


A possible explanation for the conflicting findings may relate to the experimentaldesign used to examine the effects of CrS on exercise performance. Most studies have employed a crosssectional experimental design or an ordered treatment allocation. However, few studies have utilised a crossover experimental design, possibly due to the time required for muscle TCr to return to basal levels after CrS was unknown. Lemon, (2002) indicates that a variety of factors including, but not limited to, sample size, exercise modality, rest and recovery intervals, residual effects of cessation of CrS, non-responders, gender and age effects and methodology used, make any interpretation of existing Cr literature extremely difficult.