Protein and Amino Acid Supplementation Among Recreational Gym Goers and Associated Factors—An Exploratory Study

<b>Objective:</b> The present study investigated the relationship between protein and amino acid supplementation and various associated aspects among recreational gym goers at 2 gymnasiums in Oradea (Romania). <b>Methods:</b> A total of 165 gym goers (110 men and 55 women, most of them 18-30 years old) with high educational levels were included in the present study, which was conducted as face-to-face interviews. <b>Results:</b> Participants were divided into 4 groups: protein supplement users (PSUs, 42/165), creatine supplement users (CSUs, 38/165), L-carnitine supplement users (LcSUs, 37/165), and protein + creatine + L-carnitine supplement users (PCLcSUs, 48/165). Most consumers were young (18-30 years) and preferred the triple combination. Females consumed PS and CS (38.2% and 34.5%, respectively), while the most-used NSs by males were PCLcS (36.4%) and LcS (27.3%). Obese gym goers opted for LcS consumption (r = 0.999, <i>p</i> < 0.05). Creatine and L-carnitine were consumed for force training (65.79 and 62.16%), while PCLcS and PS were used in cardio + force and force training in equal measures (42.86 and 47.92%, respectively). Most PSUs were gym goers for 7-12 months and more than 1 year (r = 0.999 and r = 0.952, respectively, <i>p</i> < 0.05), while PCLcSUs had a training frequency of at least 5 times a week (r = 0.968, <i>p</i> < 0.05). Muscle mass growth was the primary training focus for all NS users (57.89%), followed by muscular tonus (40.54%, <i>p</i> < 0.05). Almost 30% of one-only NS users reported various side effects, whereas all PCLcSUs claimed side effects (<i>p</i> < 0.05). <b>Conclusions:</b> Age and gender were key factors in diet type, training type, frequency, duration, scope, NS type, and dose intake. The frequency of side effects substantially depended on the kind of NS and the dose consumed. The present study's results highlight the need for health professionals' advice and monitoring in personalized diets and protein and amino acid supplementation in recreational gym goers.