Immediately after Manny Pacquiao’s spectacular win against a much bigger opponent in Las Vegas, Floyd Mayweather Sr. accused the Filipino boxer of using steroids.

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Manny, obviously caught by surprise by the accusation, immediately told Philippines media that he does not know what steroids are - much less what they look like.

I think it is understandable that someone will accuse Pacquiao of using performance-enhancing drugs because of the astounding way he earns his victories over bigger and taller opponents.

More often than not, he wins via a knockout. He also has a power punch that seems to defy his rather small frame and low weight. As the fight goes the full route, Pacquiao seems to get stronger and faster.

On paper, Manny is physically inferior compared to most of his opponents. In his last fight, he gave up at least three inches in height and reach.

Without a doubt, performance-enhancing drugs have been resorted to by even some of the most popular and dominating athletes. Olympic winners have been stripped of their medals after failing their drug tests.

The most celebrated case to my mind is that of Marion Jones, who had to return her five Olympic medals after her admission to doping before the Sydney Olympics. Ben Johnson too had to be stripped of his Olympic 100m gold medal after drug use in Seoul, Korea.

Alex Rodriguez, an extremely popular baseball player and Argentina soccer legend Maradona dabbled in drugs as well. More recently, former tennis champion John McEnroe hit the headlines as he admitted taking butazolidin and prednisone. He later clarified that he did not use these drugs as performance-enhancer but merely as anti-inflammatory.

Some of the more popular performance-enhancing drugs include amphetamine, ephedrine, stanzol, diuretics, hGH, testosterone and nandrolone. Anabolic steroids, which include testosterone and nandrolone, increase muscle strength by encouraging new muscle growth.

Amphetamine is a stimulant that boosts energy, mood and confidence. Diuretics, which Johnson used, are used by athletes whose events have weight restrictions like boxing. They mask the use of other drugs by flushing them out.

HGH is a protein hormone that increases muscle mass. Its use is gaining extreme popularity among athletes because it is very difficult to detect.

What many fail to notice and realise about Pacquiao’s success is the very rigid training he undergoes with coach Freddie Roach. While others rely on steroids for endurance and power, Pacquiao runs a mile, spars for ten rounds and hits the gym on a regular basis with Roach.

For me, the secret weapon and drug of Manny Pacquiao is Coach Freddie himself. Pacquiao trains diligently and seriously under the watchful and expert eyes of Roach.

This has yielded great results through the years and does not damage Manny's health like steroids and other illegal drugs. His natural training with Coach Freddie also spares Manny the embarassment of being stripped of his title.

I am inclined to believe that it is Roach who acts as Pacquiao’s performance-enhancing drug. In two weeks, as Pacquiao guns for an unprecedented seventh world title, we will again be witness to the performance-enhancing drug and agent that is Coach Freddie Roach.