Muscle hypertrophy is an increase in the size of muscle cells. It differs from muscle hyperplasia, which is the formation of new muscle cells.

A range of stimuli can increase the volume of muscle cells. Summarizing, these changes occur as an adaptive response that serves to increase the ability to generate force or resist fatigue in anaerobic conditions.

Strength training typically produces a combination of the two different types of hypertrophy: contraction against 80 to 90% of the one repetition maximum for 2–6 repetitions (reps) causes myofibrillated hypertrophy to dominate (as in powerlifters, olympic lifters and strength athletes), while several repetitions (generally 8 – 12 for bodybuilding or 12 or more for muscular endurance) against a sub-maximal load facilitates mainly sarcoplasmic hypertrophy (professional bodybuilders and endurance athletes).^{[citation needed]} The first measurable effect is an increase in the neural drive stimulating muscle contraction. Within just a few days, an untrained individual can achieve measurable strength gains resulting from "learning" to use the muscle.^{[citation needed]} As the muscle continues to receive increased demands, the synthetic machinery is upregulated. Although all the steps are not yet clear, this upregulation appears to begin with the ubiquitous second messenger system (including phospholipases, protein kinase C, tyrosine kinase, and others).^{[citation needed]} These, in turn, activate the family of immediate-early genes, including c-fos, c-jun and myc. These genes appear to dictate the contractile protein gene response.^{[citation needed]}

"Pumped Up Kicks" is a song by American indie pop band Foster the People. It was released as the group's debut single in September 2010, and the following year was included on their EP Foster the People and their debut album Torches. "Pumped Up Kicks" became the group's breakthrough hit and was one of the most popular songs of 2011. The song was written and recorded by frontman Mark Foster while he was working as a commercial jingle writer. Contrasting with the upbeat musical composition, the lyrics describe the homicidal thoughts of a troubled youth.

The track received considerable attention after it was posted online in 2010 as a free download, and it helped the group garner a multi-album record deal with Columbia Records imprint Startime International before they had issued a commercial release. The song became both a crossover hit and a sleeper hit in 2011, as it received significant airplay on modern rock and contemporary hit radio stations. The song spent eight consecutive weeks at number three on the Billboard Hot 100 chart in the United States, making it the first Billboard Alternative Songs number-one single to crack the U.S. top 5 since Kings of Leon's "Use Somebody" in 2009. The song was widely praised by critics, and it has been licensed for use in a wide range of popular media since its release. "Pumped Up Kicks" received a Grammy Award nomination for Best Pop Duo/Group Performance.

Craig Ferguson (born 17 May 1962) is a Scottish-American television host, stand-up comedian, writer, actor, director, author, and producer. He is the host of The Late Late Show with Craig Ferguson, an Emmy Award-nominated, Peabody Award-winning late-night talk show that airs on CBS. In addition to hosting that program and performing stand-up comedy, Ferguson has written two books: Between the Bridge and the River, a novel, and American on Purpose, a memoir. He became a citizen of the United States in 2008.

Before his career as a late-night television host, Ferguson was best known in the United States for his role as the office boss, Nigel Wick, on The Drew Carey Show from 1996 to 2003. He also wrote and starred in three films, directing one of them.

Ferguson was born in the Stobhill Hospital in the Springburn district of Glasgow, Scotland to Robert and Janet Ferguson, and raised in nearby Cumbernauld, growing up "chubby and bullied". When he was six months old, he and his family moved from their Springburn apartment to a council house in Cumbernauld. They lived there as Glasgow was re-housing many people following damage to the city from World War II. Ferguson attended Muirfield Primary School and Cumbernauld High School. At age sixteen, Ferguson dropped out of Cumbernauld High School and began an apprenticeship to be an electronics technician at a local factory of American company Burroughs Corporation.