I am having a strange issue with left arm. During the transition of the Russian Dip where my are is most bent I feel like my left arm is much weaker than my right. I was testing my strength at the same arm angle on a cable machine and my left arm could only lift half what my right arm could but only in that position. I have not had this issue with any of the other types of dips or pressing; only once my arm gets past 90 degrees of flexion do I notice a difference. It feels like the tendons articulate over my bones differently in my left arm and after it gets past about 90 degrees of flexion it doesn't feel weak. Has anyone else experienced this? There isn't any noticeable difference in the size of my triceps muscles; if anything my left arm is slightly bigger. Any advice or help would be great because this is severely hindering my progress.