^ Housman & Dorman 2005, pp. 303–04. "The linear model supported previous findings, including regular exercise, limited alcohol consumption, abstinence from smoking, sleeping 7–8 hours a night, and maintenance of a healthy weight play an important role in promoting longevity and delaying illness and death." Citing Wingard DL, Berkman LF, Brand RJ (1982). "A multivariate analysis of health-related practices: a nine-year mortality follow-up of the Alameda County Study". Am J Epidemiol. 116 (5): 765–75. doi:10.1093/oxfordjournals.aje.a113466. PMID 7148802.
*Pay initiation fee plus first and last months’ dues. Initiation fee ranges between $29.99-$49.99, and monthly dues range between $29.99-$99.99 per month, depending on club location and type. Pay $49.99 Annual Fee once during fourth month of enrollment and annually thereafter. Offer available online or in club. Offer applies to select One-Club Commitment memberships at Sport and Active clubs only. Offer not available at Super-Sport or Ultra-Sport clubs. Excludes All-Club, Basic, Add-On and Limited Term Prepaid memberships. One year commitment required for Commitment memberships. Selected club of enrollment must be within 50 miles of purchaser’s residence. One-Club access is for club of enrollment only. Taxes may apply. Not valid for current members. Dues must be paid by pre-authorized payment (eft). Must be at least 18 years old or 12 with parent. No other discounts with this offer. Incentives may be offered for other memberships. Facilities and amenities vary per location. Kids’ Club, Personal/Group Training, specialty classes and class reservations are available for an additional fee. Not all clubs open 24 hours every day. See club for details. Excludes select Hawaii, San Francisco Bay Area and Monterey Bay Area clubs. Valid through 11:59 (PT) on 6/9/2019. © 2019 24 Hour Fitness USA, Inc. Texas Health Studio #080501. Florida Registration Numbers HS4505, HS4504, HS7025, HS7004, HS7479, HS7621, HS7436, HS7746, HS7663, HS7776, HS7805, HS12038, HS11951, HS12546, HS12661, HS12874.
Muscle growth is more difficult to achieve in older adults than younger adults because of biological aging, which leads to many metabolic changes detrimental to muscle growth; for instance, by diminishing growth hormone and testosterone levels. Some recent clinical studies have shown that low-dose HGH treatment for adults with HGH deficiency changes the body composition by increasing muscle mass, decreasing fat mass, increasing bone density and muscle strength, improves cardiovascular parameters, and affects the quality of life without significant side effects.[unreliable medical source?]