Table 2 Summarized data collected from the selected studies.
| First Author, Year | # of subjects (gender) | Sports | Subjects’ age mean±SD [range] (yrs.), | Anthropometric data Height mean±SD (cm) Body mass±SD (Kg) Body mass index±SD (Kg m −2 ) | Interval between tests | Type of MG (description according to the studies) | Area (arch) | Cardiopulmonary Capacity | |
|---|---|---|---|---|---|---|---|---|---|
| VO 2 max Mean±SD | VE max (L/min) | ||||||||
| Bailey, 2015 4 | 15 (male) | n.r. | 24±1 [n.r] | n.r±n.r. n.r±n.r. 25.2±0.9 | At least 1 week | - (MG1) traditional boil-and-bite; - (MG2) “vented” boil-and-bite | Upper | (L/min) C*– 3.49±0.13 MG1 –3.48±0.13 MG2 –3.48±0.17 | C – 123.29±6.21 MG1 –121.94±6.45 MG2 –113.16±7.66 |
| Bourdin, 2006 7 | 19 (male) | 2 Handball, 1 ice hockey, 16 rugby | 27±4.8 [n.r.] | 180.9±8.7 91.4±18.6 n.r.±n.r. | At least 2 days | - (MG1) self-adapted thermoplastic (boil-and-bite) - (MG2) custom-made methyl methacrylate resin | Upper | (ml/Kg/min) C – 47.1±9.18 MG1 – 48.2±9.03 MG2 – 48.1±9.46 (15 subjects) | C – 144.2±19.76 MG1 – 147.4±17.21 MG2 – 148.2±18.06 (15 subjects) |
| Delaney, 2005 10 | 12 (female) | Ice hockey | 19.8±0.8 [n.r.] | 166.8±7.2 63.8±6.6 n.r.±n.r. | Average of 6.8 days | - (MG1) boil-and-bite | Upper and lower | (ml/Kg/min) C – 52.4±0.8 MG1 – 48.8±0.7 | C – 114.1±3.8 MG1 – 108.5±4.0 |
| El-Ashker, 2015 15 | 18 (male) | Elite boxer | 19.4±2.01 [17.8–24.2] | 174±7.9 74.5±5.1 n.r.±n.r. | 6–10 days | - (MG1) custom- fitted: ethylene vinyl acetate copolymer sheets, with standard thickness 4 mm - (MG2) stock MG | Upper | (ml/Kg/min) C – 47.37±5.34 MG1 – 46.48±3.65 MG2 – 40.54±5.68 | C – 99.51±13.42 MG1 – 95.71±14.82 MG2 – 92.74±11.26 |
| Francis, 1991 17 | 10 (male) 7 (female) | n.r. | 27.2±5.2 [20–37] | 175.51±9.65 72.72±15.59 n.r.±n.r. | 24–48 h | - (MG1) unfitted, made of a soft rubberized material - (MG2) unfitted, made of the same material and construction as MG - (MG3) bimaxillary guard composed of a more rigid vinyl material with a small breathing hole between the upper and lower plates. | MG1 – upper MG2 and MG3 – upper and lower | (ml/Kg/min) C – 30.46±4.37 MG1 – 27.38±5.34 MG2 – 28.1±3.47 MG3 –27.39±5.68 | C – 50.98±19.72 MG1 – 43.57±9.47 MG2 – 44.63±12.98 MG3 – 41.34±14.24 |
| Garner, 2011 21 | 13 (male) 3 (female) | n.r. | 21.2±0.75 [18–21] | 176.37±7.3 75.2±12.96 n.r.±n.r. | 2–3 days | - (MG1) custom-fitted | Lower | (ml/Kg/min) C1 – 24.8±5.8 MG1 – 31.19±7.5 (14 subjects) | C – 58.3±13.7 MG1 – 56.9±11.5 (14 subjects) |
| Garner, 2015 19 | 21 (n.r.) | n.r. | n.r. [18–21] | n.r. n.r. n.r. | At least 3 days | - (MG1) boil-and-bite - (MG2) polypropylene, custom-fit - (MG3) ethylene vinyl acetate, custom-fit | Lower | (ml/Kg/min) C – 30.59±3.24 MG1– 29.98±4.42 MG2– 30.59±4.76 MG3– 30.64±4.35 (16 subjects) | C – 45.60±7.50 MG1 – 42.93±7.11 MG2 – 46.02±8.60 MG3 – 45.26±7.67 (16 subjects) |
| Gebauer, 2011 22 | 27 (male) | Hockey or water polo | 23.5±3.8 [n.r.] | 182±0.08 81.7±8.6 24.6±2.1 | 1 week | - (MG1) custom laminated MG with normal palatal surface - (MG2) custom laminated MG with palatal coverage up to the gingival margin | Upper | (ml/Kg/min) C – 56.09±4.82 MG1 – 57.22±6.14 MG2 – 56.76±6.33 | C – 124.19±15.62 MG1 –122.51±18.80 MG2 –124.22±14.68 |
| Kececi, 2005 28 | 11 (male) 11 (female) | Elite taekwondo athletes | 16±1.11 [14–17] | n.r.±n.r. n.r.±n.r. n.r.±n.r. | 48 h | - (MG1) custom- made EVA | Upper | (ml/Kg/min) C – 51.79±2.12 MG1– 52.73±1.81 | C – 106.32±5.75 MG1 – 108±4.41 |
| Piero, 2015 36 | 10 (male) | Amateur road cyclists | 34±6 [n.r.] | 178±7 70±10 22±2 | 1 week | - (MG1) custom-made | Upper and lower | (ml/Kg/min) C – 57.8±6.5 MG1 – 58.1±5.8 | C – 140±23 MG1 – 141±22 |
| Rapisura, 2010 39 . | 11 (female) | n.r. | 22±3.3 | 159.8±4.3 n.r. 63.7±8.9 | Average of 9.1 days | - (MG1) universal self-adapted MG (boil-and-bite) - (MG2) self-adapted MG made for women (boil-and-bite) | MG1 – upper MG2 – upper and lower | (mll/Kg/min) C – 31.0±6.7 MG1 – 30.4±7.1 MG2 – 29.6±5.4 | C – 68.5±17.3 MG1 – 64.7±13.2 MG2 – 56.8±6.4 |
| von Arx, 2008 41 | 13 (male) | n.r. | 22±n.r. [18–27] | n.r.±n.r. n.r.±n.r. n.r.±n.r. | 48 h | - (MG1) multiple-EVA pressure-laminated MG | Upper | (L/min) C – 3.29±0.36 MG1 – 3.16±0.49 | C – 112.9±28.3 MG1 – 105.3±17.8 |
| Wenta, 2014 44 | 6 (male) 1 (female) | n.r. | 19.4±1.6 [n.r.] | 175±2 5 79.4±8.89 n.r. | 7 days | - (MG1) self-adapted (boil-and-bite) | n.r. | (ml/Kg/min) C – 27.8±n.r. MG1 – 27.9±n.r. | C – 57.75±n.r. MG1 – 56.77±n.r. |
| Yarar, 2013 45 | 8 (male) | Combat sports | 22±2.2 [n.r.] | 173.5±3.38 70.45±8.14 n.r. | 1 week | - (MG1) MG (non-specified) | n.r. | (ml/Kg/min) C – 53.87±6.42 MG1 – 53.37±5.57 | n.r. |
C* – Control (without mouthguard); n.r.: not reported