Exercise Science Program, Department of Physical Therapy, Marquette University, Milwaukee, WI.
Department of Obstetrics and Gynecology, Medical College of Wisconsin, Milwaukee, WI.
Med Sci Sports Exerc. 2018 Aug;50(8):1558-1569. doi: 10.1249/MSS.0000000000001609.
To determine whether postpartum women (vaginal and cesarean delivery) have deficits in trunk flexor strength, fatigability and steadiness, compared with nulligravid women, up to 26 wk postpartum. We hypothesized that postpartum women would be weaker, more fatigable, and have greater torque fluctuations than controls, with cesarean delivery showing greater deficits than vaginal delivery.
Twenty-two control women (nulligravid) and 29 postpartum women (20-40 yr, 19 who delivered via vaginal birth, 13 via Caesarian section) participated. Postpartum women were tested 8 to 10 wk and 24 to 26 wk postpartum. Control women were tested 16 to 18 wk apart. Maximal voluntary isometric contractions (MVC) were performed at multiple trunk positions with the trunk flexor muscles. To determine trunk flexor fatigability, subjects performed intermittent isometric contractions at 50% MVC (6-s contraction, 4-s rest) in upright sitting until task failure. An MVC was performed during the fatiguing task (one per minute) and at 10 and 20 min of recovery.
At 8 and 26 wk, postpartum women (groups pooled) were weaker at all trunk angles (38% and 44% respectively, P < 0.05) than controls despite no differences in handgrip strength. Postpartum women were more fatigable (71% and 52% respectively) and had greater torque fluctuations than controls (P < 0.05). At 8 wk postpartum, women who had a cesarean delivery, were 59% more fatigable (P = 0.004) than the vaginal delivery group, with no difference between delivery types at 26 wk postpartum.
Musculoskeletal recovery, including trunk flexor muscle strength and fatigability, is incomplete at 26 wk postpartum. These findings provide a rationale for future studies to address outcomes of rehabilitation programs specifically targeted at improving strength and fatigability of the trunk flexor muscles after pregnancy and childbirth.
确定与未生育女性相比，产后女性（阴道分娩和剖宫产）在产后 26 周内是否存在躯干屈肌力量、疲劳性和稳定性缺陷。我们假设，与对照组相比，产后女性的力量更弱，更容易疲劳，扭矩波动更大，剖宫产的缺陷大于阴道分娩。
22 名对照组（未生育）和 29 名产后女性（20-40 岁，19 名阴道分娩，13 名剖宫产）参与了研究。产后女性在产后 8-10 周和 24-26 周进行测试。对照组女性在 16-18 周之间进行测试。通过躯干屈肌进行多次躯干位置的最大等长收缩（MVC）测试。为了确定躯干屈肌疲劳性，受试者在直立坐姿下以 50% MVC（6 秒收缩，4 秒休息）进行间歇性等长收缩，直到任务失败。在疲劳任务期间（每分钟一次）以及恢复 10 和 20 分钟时进行一次 MVC。
在 8 周和 26 周时，产后女性（两组合并）在所有躯干角度的力量都较弱（分别为 38%和 44%，P<0.05），尽管手握力没有差异。与对照组相比，产后女性更容易疲劳（分别为 71%和 52%），扭矩波动更大（P<0.05）。在产后 8 周时，剖宫产的女性比阴道分娩组更容易疲劳 59%（P=0.004），而在产后 26 周时，两种分娩方式之间没有差异。
在产后 26 周时，肌肉骨骼的恢复，包括躯干屈肌力量和疲劳性，还不完全。这些发现为未来的研究提供了依据，以确定专门针对改善妊娠和分娩后躯干屈肌力量和疲劳性的康复方案的结果。
