Table 1.

Summary of the methods and results of included studies.

Study	Sample	Design	RT Protocol	CR Protocol	Duration	Results
Bernat et al. [37]	24 older, untrained men	Random assignment to 1 of 2 groups: (1) CR + RT; (2) PLA + RT	Total body unsupervised protocol performed 2 d/wk consisting of 3–4 sets per exercise at 80% 1 RM with 2 min inter-set rest intervals	0.1 g/kg/d consumed post-training and at participants’ leisure on non-training days	8 wks	−Similar between-group changes in muscle thickness of the elbow flexors, elbow extensors, knee flexors, and knee extensors
Candow et al. [33]	38 young, physically active, untrained men and women	Random assignment to 1 of 4 groups: (1) CR + RT performed twice/wk; (2) CR + RT performed thrice/wk; (3) PLA + RT performed twice/wk; (4) PLA + RT performed thrice/wk	Total body protocol performed 2–3 d/wk consisting of 2–3 sets per exercise of 10 repetitions with 1–2 min inter-set rest intervals	0.15 g/kg/d for participants in 2 d/wk RT and 0.10 g/kg for participants in 3 d/wk RT; no mention of supplementation on non-training days	6 wks	−Superior increases in elbow flexor muscle thickness in the CR + RT groups (16–20%) compared to PLA + RT groups (2–6%). −Superior increases in elbow extensor muscle thickness in the CR + RT groups (26–27%) compared to PLA + RT groups (11–13%) −Similar increases in knee flexor muscle thickness in CR + RT groups (10–17%) and PLA + RT groups (6–15%) −Superior increases in knee extensor muscle thickness in CR + RT groups (11–12%) compared to PLA + RT groups (3–5%)
Candow, Chilibeck, Gordon, Vogt et al. [38]	46 older, untrained men	Random assignment to 1 of 2 groups: (1) CR + RT; (2) PLA + RT	Total body supervised protocol performed 3 d/wk consisting of 3 sets of 10 repetitions per exercise at 80% 1 RM	0.1 g/kg/d consumed in 2 equal doses pre- and post-training and with food on non-training days	12 months	−Similar between-group changes in muscle thickness of the elbow flexors, elbow extensors, knee flexors, knee extensors, ankle plantarflexors, and ankle dorsiflexors
Candow et al. [39]	25 older, untrained men	Random assignment to 1 of 2 groups: (1) CR + RT; (2) PLA + RT	Total body supervised protocol performed 3 d/wk consisting of 3 sets of 10 repetitions with 2 min inter-set rest intervals	0.1 g/kg/d consumed in 3 equal doses pre- and post-training and before bed on training days; no supplementation on non-training days	10 wks	−Superior increases in elbow extensor muscle thickness in the CR + RT group (11.6%) compared to the PLA + RT group (1.4%) −Superior increases in knee flexor muscle thickness in the CR + RT group (9.4%) compared to the PLA + RT group (3.2%) −Superior increases in knee extensor muscle thickness in the CR + RT group (11.3%) compared to the PLA + RT group (5.8%) −Superior increases in ankle plantarflexor muscle thickness in the CR + RT group (13.8%) compared to the PLA + RT group (8%) −Similar between-group changes in muscle thickness of the elbow flexors and ankle dorsiflexors
Candow, Chilibeck, Gordon & Kontulainen [42]	52 older, untrained men and women	Random assignment to 1 of 2 groups: (1) CR + RT; (2) PLA + RT	Total body supervised protocol performed 3 d/wk consisting of 3 sets of 10 repetitions per exercise	0.1 g/kg/d consumed in 2 equal doses pre- and post-training and with food on non-training days	12 months	−Similar between-group changes in muscle CSA of the forearm and lower leg
Chilibeck et al. [40]	33 postmenopausal, untrained women	Random assignment to 1 of 2 groups: (1) CR + RT; (2) PLA + RT	Total body supervised protocol performed 3 d/wk consisting of 3 sets of 10 repetitions per exercise	0.1 g/kg/d consumed in 2 equal doses pre- and post-training and with food on non-training days	12 months	−Similar between-group changes in muscle thickness of the elbow flexors, elbow extensors, knee flexors, knee extensors, ankle plantarflexors, and ankle dorsiflexors
Mills et al. [34]	22 young, recreationally trained men and women	Random assignment to 1 of 2 groups: (1) CR + RT; (2) PLA + RT	Total body protocol performed 5 d/wk consisting of 3 sets per exercise of 6–10 repetitions with 2 min inter-set rest intervals	0.1 g/kg/d consumed during training sessions (5 d/wk); no supplementation on non-training days	6 wks	−Similar between-group changes in muscle thickness of the biceps brachii, triceps brachii, quadriceps femoris, hamstrings, and gastrocnemius
Pakulak et al. [36]	13 young, resistance-trained men and women	Random assignment to 1 of 2 groups: (1) CR + RT; (2) PLA + RT	Total body protocol performed 4 d/wk consisting of 3 sets per exercise of 6–10 repetitions with 2 min inter-set rest intervals	0.1 g/kg/d consumed 60 min prior to training sessions (4 d/wk); no supplementation on non-training days	6 wks	−Superior increases in knee extensor muscle thickness in the CR + RT groups (10.8%) compared to PLA + RT groups (5.7%) −Similar between-group changes in muscle thickness of the elbow flexors, elbow extensors, and knee flexors
Roschel et al. [41]	88 elderly, pre-frail and frail men and women	Random assignment to 1 of 4 groups: (1) CR + RT; (2) PLA + RT; (3) CR + Whey + RT; (4) Whey + RT	Total body supervised protocol performed 2 d/wk consisting of 2–4 sets at 50–70% 1 RM	6 g/d in CR + RT and 6 g/d + 30 g Whey in CR + Whey + RT; supplements consumed 7 d/wk	16 wks	−Similar between-group changes in muscle CSA of the vastus lateralis
Sousa-Silva et al. [35]	17 young, untrained men	Random assignment to 1 of 2 groups: (1) CR + RT; (2) PLA + RT	Unilateral elbow flexion protocol (2 d/wk): One arm of each participant performed the biceps curl combined with blood flow restriction for 4 sets of 15–30 reps at 30% 1 RM with 30 s inter-set rest intervals and the other arm performed the biceps curl without blood flow restriction for 4 sets of 10–12 repetitions at 70% 1 RM with 2 min inter-set rest intervals	20 g/d consumed for the first 5 days followed by 5 g/d consumed post-training and during regular training time on non-training days	8 wks	−Superior increases in elbow flexor muscle thickness in CR + RT (17%) compared to PLA + RT (9%)

Abbreviations: CR: creatine; PLA: placebo; and RT: resistance training.