PMID 24724089

Research
All papers

High-Intensity Interval Training in Patients with Substance Use Disorder

Flemmen G, Unhjem R, Wang E

Question

Can patients with substance use disorder in residential clinical treatment adhere to and benefit from supervised high-intensity interval treadmill training compared with conventional rehabilitation activities?

Summary

This randomized clinical study tested whether residential patients with substance use disorder could complete supervised treadmill HIIT and whether it improved aerobic fitness more than conventional rehabilitation activities. The HIIT group performed 4 x 4 minute intervals at 90-95% of maximal heart rate, 3 days per week for 8 weeks. Participants who completed HIIT attended 22 +/- 1 of 24 sessions, reached the target intensity in all completed sessions, reported no problems beyond normal strain, and improved VO2max by 15 +/- 7%, while the conventional rehabilitation control group did not improve VO2max.

Methodology

  • Adults in residential treatment for ICD-10 F10-F19 substance use disorder due to illegal drug abuse.
  • 24 participants.
  • Inclined treadmill walking or running.
  • Work intervals: 4 minutes at 90-95% HRmax.
  • Recovery: 3 minutes at approximately 70% HRmax.
  • Intensity: 90-95% HRmax during work intervals; target reached in all completed sessions.
  • At least 25 minutes of interval/recovery time; warm-up/cooldown not reported.
  • 3 days/week.
  • 8 weeks.
  • Randomized controlled clinical intervention with high-intensity interval treadmill training versus conventional rehabilitation control.
  • VO2max, Work economy, Insomnia, anxiety, and depression, and Training feasibility and tolerability were tracked.

Outcomes

VO2max

TG improved VO2max by 15 +/- 7%, from 42.3 +/- 7.2 to 48.7 +/- 9.2 mL/kg/min; CG changed from 41.8 +/- 12.3 to 42.6 +/- 12.1 mL/kg/min.

TG within-group P < 0.01; change differed from CG, figure reports between-group change P < 0.05 and table marks P < 0.05.

Improved

Work economy

No significant between- or within-group differences in work economy after training.

No clear change

Training adherence

HIIT completers carried out 22 +/- 1 of 24 scheduled sessions and reached target intensity in all completed sessions.

Improved

Psychological symptoms

Depression decreased within TG and anxiety decreased within CG, but no between-group differences were observed for insomnia, anxiety, or depression.

Within-group depression change in TG P < 0.05; within-group anxiety change in CG P < 0.05.

Mixed

Insights

  • A supervised 4 x 4 minute treadmill HIIT protocol can be feasible in a medically screened residential SUD population.
  • Heart-rate-monitored progression is important: speed and incline were adjusted to keep participants at 90-95% HRmax.
  • The evidence supports aerobic fitness improvement, not superiority for insomnia, anxiety, or depression.

Limitations

  • Small sample with 24 randomized and 16 completers.
  • Clinical SUD population limits generalization to general app users.
  • Comparator was heterogeneous, lower-intensity clinical activity rather than time- or energy-matched exercise.
  • Training was supervised in a residential clinic, limiting direct translation to unsupervised settings.
  • Warm-up and cooldown for training sessions were not explicitly reported.

Safety

  • None of the subjects reported problems or discomfort completing HIIT sessions other than normal strain following high-intensity exercise.
  • No commenced training session was aborted.
  • Participants with cardiovascular disease or COPD were excluded.