Endurance Research Group, School of Sport and Exercise Science, University of Kent, Chatham, United Kingdom.
Endurance Research Group, School of Sport and Exercise Science, University of Kent, Chatham, United Kingdom.
Neurosci Lett. 2021 Jan 19;743:135584. doi: 10.1016/j.neulet.2020.135584. Epub 2020 Dec 19.
Transcranial direct current stimulation (tDCS) is a neuromodulatory tool purported to enhance endurance performance through reducing fatigue related perceptions, including exercise-induced pain (EIP). We examined whether tDCS of the left DLPFC (1) can reduce EIP during a fixed intensity cycling trial (FI), (2) can improve cycling time trial (TT) performance, and (3) whether this was affected by a bilateral or an extracephalic montage. This investigation was comprised of two parts (study one and two). In both studies, participants completed a 10-minute FI trial and a 15-minute TT after 10 min of 2 mA anodal left DLPFC tDCS, SHAM or no stimulation. In study one, 11 participants received tDCS via a bilateral montage. In study two, 20 participants received tDCS using an extracephalic montage. Pain was recorded throughout the FI and TT trials, with power output (PO) monitored during the TT. Study one saw no significant changes in pain (tDCS 4.3 ± 2.0; SHAM 4.0 ± 1.8; control 3.8 ± 1.4) during the FI trial and no significant differences in distance covered, pain or PO in the TT. In study two there were no differences in pain reported in the FI trial, or distance covered (P = 0.239), pain or PO in the TT. In summary, tDCS of the DLPFC did not induce analgesia and provided no ergogenic effect for TT performance, moreover these observations were consistent across both the extracephalic and bilateral montage. These findings are in line with an increasing number of studies demonstrating the inconsistent effects of tDCS.
经颅直流电刺激（tDCS）是一种神经调节工具，据称可通过减少与疲劳相关的感知，包括运动引起的疼痛（EIP），来提高耐力表现。我们研究了左背外侧前额叶皮层（DLPFC）的 tDCS 是否可以：（1）减少固定强度自行车试验（FI）中的 EIP；（2）提高自行车计时赛（TT）的表现；以及（3）这种影响是否受到双极或颅外刺激模式的影响。本研究包括两个部分（研究一和研究二）。在两项研究中，参与者在接受 2 mA 阳极左 DLPFC tDCS、假刺激或无刺激 10 分钟后，完成了 10 分钟 FI 试验和 15 分钟 TT。在研究一中，11 名参与者接受了双极刺激模式的 tDCS。在研究二中，20 名参与者接受了颅外刺激模式的 tDCS。在 FI 和 TT 试验中记录了疼痛，在 TT 期间监测了功率输出（PO）。研究一未观察到 FI 试验中疼痛有显著变化（tDCS 4.3 ± 2.0；SHAM 4.0 ± 1.8；对照 3.8 ± 1.4），TT 中也没有距离、疼痛或 PO 的显著差异。在研究二中，FI 试验中报告的疼痛或 TT 中距离、疼痛或 PO 没有差异（P = 0.239）。总之，DLPFC 的 tDCS 没有引起镇痛作用，也没有对 TT 表现产生促进作用，此外，这些观察结果在颅外和双极刺激模式中是一致的。这些发现与越来越多的研究结果一致，这些研究结果表明 tDCS 的效果不一致。
