Table 2 Study characteristics
Study | Study design | Blinding | Patients (M:F) | Level of fitness/study population | Medication dose | Dose timing | Groups (N =) | Age | Dropout rate | Performance measures |
|---|---|---|---|---|---|---|---|---|---|---|
Dufka et al. [16] | RCT | Double blind, randomized | 12 (sex breakdown unknown) | High school students | L-methamphetamine 16, 48 mcg | Immediately prior to test | L-methamphetamine 4 or 12 inhalations (N = 12) | 14–17 (no mean provided) | 0 | Miles travelled in 20 min on stationary bike |
Placebo (N = 12) | ||||||||||
Altszuler et al. [18] | RCT | Double blind, randomized | 54:19 | Kids with ADHD diagnoses in a summer training program | Methylphenidate 21 mg | Daily for 3 weeks, then for final 3 weeks also attended sports training program for badminton | Methylphenidate (Concerta or Focalin) (N = 37) | 7.99 ± 1.7 | 0 | Playing badminton (sports skills in underhands, backhands, overheads, serves; sport knowledge; staff ratings from summer treatment program counselors; behavioral assessment in rule violations, game awareness, name-calling peers, verbal abuse to staff, and complaining) |
Placebo (N = 36) | ||||||||||
King et al. [19] | RCT, crossover | Double blind | 9:6 | Unknown; right—handedness required | Methylphenidate IR 20 mg | Prior to test (time not specified) | Methylphenidate 20 mg (N = 15) | 28.4 ± 5.2 | 0 | Handgrip task |
placebo (N = 15) | ||||||||||
Roelands et al. [20] | RCT, crossover | Double blind, randomized | 8:0 | Well-trained cyclists | Methylphenidate 20 mg | 1 h prior to test | Methylphenidate 20 mg (N = 8) | 26 ± 5 | 0 | Cycling time to complete a timed trial at 18C and 30C |
Placebo (N = 8) | Core temperature, blood (cortisol, growth hormone, ACTH, beta-endorphin, hematocrit) | |||||||||
Cordery et al. [21] | RCT, crossover | Double blind, randomized | 0:9 | Active, participate in regular endurance exercise training | Bupropion 150 mg × 4 | Before bed the night before and upon wakening morning of test | Bupropion 150 mg (N = 9) | 21 ± 2 | 0 | Cycle at 60% VO2peak for 60 min, followed by 30 min performance test, at 30C |
Placebo (N = 9) | Core temperature, O2 consumption, CO2 production, respiratory exchange ratio | |||||||||
Piacentini et al. [22] | RCT, crossover | Double blind, randomized | 8:0 | Well trained cyclists | Bupropion 600 mg | Taken night before and 6 h before test | Bupropion (N = 8) | 24 ± 2 | 0 | Maximal power output, endurance performance tests (timed trials) |
Placebo (N = 8) | VO2 max, HR, ACTH, prolactin, cortisol, growth hormone, beta-endorphins, catecholamines | |||||||||
Roelands et al. [23] | RCT, crossover | Double blind, randomized | 8:0 | Trained cyclists | Bupropion 150/300 mg | Bupropion 150 × 3 days daily, then 300 mg × 7 days (150 mg in am and in pm) | Bupropion 150/300 mg (N = 8) | 27 ± 5 | 0 | Fixed cycle intensity exercise for 60 min followed by timed trial, at 30C |
Placebo (N = 8) | Core temperature, HR, hormones (growth hormone, cortisol, ACTH, prolactin), rating of perceived exertion | |||||||||
Chandler and Blair [17] | RCT | Double blind, randomized | 6:0 | College students, former high school athletes | Amphetamine sulfate 15 mg per 70 kg of bodyweight (mean dose 16.59 mg) | Ingestion 2 h and 5 h before testing | Dexedrine (N = 6) | 21.5 ± 2.5 | 0 | Strength (elbow flexion and knee extension strength), muscular power (bicycle ergometer, in total time to execute 5 revolutions), running speed (30 yard sprint time), acceleration, time to exhaustion |
Placebo (N = 6) | HR, respiratory exchange ratio, lactic acid, aerobic power, aerobic capacity (VO2max) | |||||||||
Mahon et al. [24] | Controlled trial | Unblinded, unrandomized | 18:0 | Average, prior diagnosis of ADHD required | Varied dose and medication type | 12–24 h prior to test and 1–2 h prior to test | Methylphenidate or amphetamine (N = 14) | 10.9 ± 1.1 | 4 | Cycle ergometer at 25, 50, and 75 W for 3 min each |
Placebo (N = 14) | Heart rate, peak VO2, Ve/VO2, respiratory exchange ratio, rating of perceived exhaustion |