Table 1 The characteristics of included 6 studies
Authors | Country | Duration | Age | PA before study initiation | PA during the study period | Exercise | Subjects (n-exp/n-con) | Intervention | Control | Measurement tools | Outcomes |
|---|---|---|---|---|---|---|---|---|---|---|---|
Bermon, 1998 [25] | Â | Â | Â | ||||||||
  Bermon, 1998 (A) [25] | France | 52 days | 67–82 | Low PA | Low PA | No | 8/8 | 20 g/d(5 days)+ 3 g/d(47 days) creatine monohydrate | 7 g glucose (4 times/day for 5 days)+ 5 g glucose(once a day for 47 days) | Adjusted muscle cross-section integration(accounting for skin and fat via skin-fold) | MM: lower limb muscular volume; MS: 1-RM, 12-RM and IIE of three major muscle groups |
  Bermon, 1998(B) [25] | France | 52 days | 67–82 | Low PA | Trained | The strength training programme (three sets of eight repetitions at 80% of one-repetition maximum, for leg press, leg extension and chest press, 3 days a week) | 8/8 | 20 g/d(5 days)+ 3 g/d(47 days) creatine monohydrate | 7 g glucose (4 times/day for 5 days)+ 5 g glucose(once a day for 47 days) | Adjusted muscle cross-section integration(accounting for skin and fat via skin-fold) | MM: lower limb muscular volume; MS: 1-RM, 12-RM and IIE of three major muscle groups |
  Buckinx, 2020 [15] | Canada | 12 weeks | ≥ 60 | Sedentary and inactive | Trained | High-intensity interval training for 12 weeks, three session of 30 min each week. | 23/21 | 10 g L- citrulline | 10 g maltodextrin | pQCT | MM:LBM, ALM; MS: HGS, leg power; PP: TUG, chair stand test, alternate-step test, balance test, 4MWT, 6MWT. |
  Chalé, 2013 [16] | America | 6 months | 70–85 | Sedentary | Trained | Resistance training three times per week for 6 months. | 42/38 | 40 g/d whey protein concentrate | 46 g/d isocaloric control. | DEX, CT | MM: LBM, ALM, leg Lean, arm lean, truck lean; MS: knee extensor strength, knee flexor strength; PP: short physical performance battery, TUG, the 5-item physical performance Battery |
Deutz, 2013 [17] | Â | Â | Â | ||||||||
  Deutz, 2 2013(B) [17] | America | 63 days | 60–76 | Fully functional with no mobility limitations | bed rest for 10 days | No | 11/8 | β-hydroxy-β-methylbutyrate (calcium salt, 1.5 g twice daily e total 3 g/day) | Placebo | DEX | MM: LBM, ALM, leg Lean, arm lean, truck lean; MS: knee extensor strength, knee flexor strength; PP: SPPB, TUG, the 5-item physical performance Battery |
  Deutz, 2013(B) [17] | America | 63 days | 60–76 | After the bed rest for 10 days | Trained | Rehabilitation program (resistance training 3×/week) 8 weeks | 11/8 | β-hydroxy-β-methylbutyrate (calcium salt, 1.5 g twice daily, total 3 g/day) | Placebo | DEX | MM: LBM, ALM, leg Lean, arm lean, truck lean; MS: knee extensor strength, knee flexor strength; PP: SPPB, TUG, the 5-item physical performance Battery |
  Dirks, 2014 [19] | Netherlands | 7 days | 69 ± 1 | no prior prolonged resistance exercise in past 6 months | One-legged knee immobilization for 5 days | No | 11/12 | a high whey protein leucineenriched oral nutritional supplement (twice daily, 10 drinks in total, each drink provide 21 g protein) | Without supplement | CT, DXA scan leg extension machine. | Quadriceps CSAs, single leg 1-RM. |
  Ferrando, 2010 [22] | America | 52 days | > 60 | Moderately active | Bed rest for 10 days | No | 10/12 | Essential amino acid supplemental 45 g (15 g TID) of amino acids. | Placebo | DEXA | LBM, leg lean mass, stair ascent power, stair descent power. |