Kerning subscripts [duplicate]

\newcommand{\EQ}{$$} \newcommand{\EN}{$$}
\EQ
\vec{F}_{TOTAL} = \vec{F}_g + \vec{F}_{OTHER}
\EN


The small g after F looks like it's hanging in space. Using

\EQ
\vec{F}_{\hspace{-0.2ex}TOTAL} = \vec{F}_{\hspace{-0.4ex}g} +
\vec{F}_{\hspace{-0.3ex}OTHER}
\EN


works, but seems a little inefficient, and requires different numbers for different subscripts. Is there any other way of dealing with this?

added: minimal working program with \mkern

\documentclass[10pt, twoside]{book}
\usepackage[utf8]{inputenc}
\usepackage{microtype}

\usepackage[USenglish]{babel}

\usepackage[T1]{fontenc}
\usepackage[urw-garamond]{mathdesign}
\usepackage{garamondx}
\usepackage{amsmath, amsthm} %, amssymb}
\newcommand{\EQ}{$$} \newcommand{\EN}{$$}

\renewcommand{\vec}[1]{\mathbf{#1}}

\newcommand{\vecdd}[1]{\ddot{\mathbf{#1}}} %bold vector with double derivatvie dot

\begin{document}

\EQ
\vec{F}_{\mkern -2mu TOTAL} = \vec{F}_{\mkern -5mu gn} + \vec{F}_{\mkern -2mu OTHER}
\EN
\end{document}

• I prefer the default look to your kerned version, especially for the OTHER term. Also, you should use \mkern{-x mu} (where x is a number) instead of \hspace, because \hspace inserts stretchable glue, which you don't want with a kern. A mu is the math unit of kerning, as opposed the \kern which kerns text. – Steven B. Segletes Jan 21 '14 at 0:47
• The subscripts starting with capital letters do look OK, but the uncapitalized g and n looked a little lost in space. The \hspace worked, but I think the \mkern is better; at the least it requires less typing. I'm a little new to latex, so I'm not exactly sure what this 'glue' you speak of is, but if it is saved, I'm all for it. – Ron Jan 21 '14 at 1:14
• You need no kern, but that those subscripts are enclosed in \textnormal, because they should be in upright type; definitely not in math italic, in any case. – egreg Jan 21 '14 at 8:52