James Jackson Jeffries was an American professional boxer who was the World Heavyweight Champion from 1899 to 1905. He was known for his enormous strength and power. Jeffries used a technique taught by his trainer Tommy Ryan where he fought out of a crouch with his left arm extended, allowing him to have powerful one-punch knockout power with his left hook. After retiring undefeated in 1905, Jeffries made a comeback in 1910 but lost the fight against Jack Johnson in Reno, Nevada, marking the end of his boxing career.

2.  James Jackson
Jeffries, byname the
Boilermaker (born April 15,
1875, Carroll, Ohio, U.S. died March 3, 1953, Burbank,
California), an American
professional boxer and
former World Heavyweight
Champion. He was known for
his enormous strength.

3.  As a powerfully built and athletic teenager, Jeffries
boxed as an amateur until age 20, when he started
fighting professionally. Already in 1899, the athlete
won the title of the champion at the heavyweight
championship held by Bob Fitzsimmons at Coney
Island. The road to the heavyweight championship
was now open for Jeffries. Using a technique taught to
him by his trainer, former Welterweight and
Middleweight Champion Tommy Ryan, Jeffries fought
out of a crouch with his left arm extended forward. A
natural left-hander, he possessed one-punch knockout
power in his left hook.

4.  James Jackson Jeffries was the
world heavyweight champion from June 9, 1899, when
he knocked out Bob Fitzsimmons in 11 rounds at
Coney Island, New York City, until 1905, when he
retired undefeated.
 In 1905, the Undefeated World Champion retired from
boxing. After several years in retirement, Jeffries was
encouraged to make a comeback and in 1910 he
returned to the ring. It was then that he lost the fight
against Jack Johnson in Reno, Nevada.

6.  The biography of James Jeffries
was not particularly boxing
gloss. However, the athlete had
outstanding power, strength,
endurance, stamina,
determination. James Jackson
Jeffries is regarded by some
fight historians as the single
greatest heavyweight in
history. He was notable for
excellent physique (height 189
cm, weight about 100 kg).
Being not very fast, he worked
his way of defense that became
the "hallmark" of many
American boxers of the early
20th century.

7.  James Jackson Jeffries was a fearsome and intimidating
fighter who established plenty of credentials for
himself in just 21 professional prizefights.
 This athlete has inspired me to exercise, because he
had the good human qualities that would be useful to
people nowadays. Positive relation to his competitors,
integrity and perseverance makes James the idol of
millions.