Table 2.

Characteristics of the studies reporting the use of isometric exercise training (IET) interventions in postoperative care settings and the outcomes of such interventions.

Reference	Study design	Surgery	Patients, N	Intervention(s)	Duration of intervention(s)	Postoperative outcomes
Tapia et al [26]	Randomized controlled trial	Autologous arteriovenous fistula for hemodialysis in the upper limbs	60	IET or control	8 weeks	IET showed an increase in hand grip and better main Doppler ultrasound maturation measurements
Tapia et al [27]	Randomized controlled trial	Hemodialysis	27	IET or control	8 weeks	IET showed an increase in hand grip and clinical and Doppler ultrasound maturation measurements
Taufik et al [28]	Randomized controlled trial	Nonarticular tibia fracture	32	IET and ROMEa or ROME only	IET and ROME: 3 times per day; ROME: 1 time per day	IET showed higher mean bone-specific alkaline phosphatase levels and lower Hummer scale callus scores
Hong and Lee [29]	Case study	Total knee replacement	1	VRb training with ROME, IET, and PTc	One 60-min session	Improved muscle strength, proprioception, balance, and gait ability
Auerbach et al [30]	One-group pretest-posttest	Heart transplantation	36	IET and control	One 3-min session	IET group had reduced/unchanged Doppler aortic flow parameters
Sisk et al [31]	Randomized controlled trial	Anterior cruciate ligament reconstruction	24	ESd and IET or IET alone	IET: 3 times a day for 6 weeks; ES: 8 hours a day, 7 days per week for 6 weeks	No difference in isometric quadriceps strength
Huikuri et al [32]	Randomized controlled trial	Aortic valve replacement	26	Chronic aortic regurgitation and control	IET handgrip test before and after surgery	Left ventricular mass regression was smaller in patients with the most depressed ventricular responses to preoperative exercise
Huikuri and Takkunen [33]	Nonrandomized controlled trial	Mitral valve surgery	28	Groups based on mean mitral valve pressure increase during IET (>4 mmHg or ≤4 mmHg)	IET handgrip test before and after surgery	Positive correlation between the change in mean mitral valve pressure gradient during IET and changes in left ventricular functioning during exercise
Huikuri et al [34]	Randomized controlled trial	Mitral valve replacement	24	Mitral regurgitation and control	IET handgrip test before and after surgery	Positive correlation between ejection fraction changes preoperatively and postoperative resting ejection fraction changes
Huikuri [35]	One-group pretest-posttest	Mitral valve replacement	11	Mitral regurgitation	IET handgrip test before and after surgery	Improved ventricular function after surgery and left ventricular response to stress caused by IET
Tapia et al [36]	Randomized controlled trial	Native vascular access maturation for chronic kidney disease	67	IET and control	8 weeks	IET showed an increase in hand grip and improved clinical and Doppler ultrasound maturation measurements
Tal-Akabi et al [37]	Randomized controlled trial	Lower limb surgery	62	High-intensity or regular-intensity strength IET	3 weeks	High-intensity IET group lifted a greater maximal lift
Martinez Carnovale et al [38]	Randomized controlled trial	Radiocephalic arteriovenous fistula maturation	36	ES and IET or IET alone	8 weeks	ES and IET group had increased clinical and Doppler ultrasonography maturation measurements
Vaegter et al [39]	Randomized controlled trial	Total knee replacement	14	Cold pressor stimulation with aerobic IET	2 sessions (before surgery and 6 months postoperative)	Association between preoperative exercise–induced hypoalgesia and postoperative pain relief
Shaw et al [40]	Randomized controlled trial	Anterior cruciate ligament reconstruction	103	IET and control	Every day for 2 weeks	IET improved knee flexion and extension range, reduced symptom scores and sports-related postoperative problems, and lower incidence of abnormal knee laxity
Sashika et al [41]	Randomized controlled trial	Total hip arthroplasty	23	IET and ROME or control	6 weeks	IET improved maximum isometric torque on both hip sides, gait speed, and cadence
Rosenfeldt et al [42]	Randomized controlled trial	Cardiac surgery	117	IET and relaxation or control	30 min IET and 20 min relaxation 3 times per week for 2 weeks	No significant changes in quality of life, rates of postoperative atrial fibrillation, or length of hospital stay

^aROME: range of motion exercise.

^bVR: virtual reality.

^cPT: physical therapy.

^dES: electrical stimulation.